Panel_14488 Panel_14488 8:00 AM 11:50 AM

Panel_15810 Panel_15810 8:00 AM 12:00 AM

The Upper Jurassic-Lower Cretaceous Vaca Muerta Formation (VMF) in the Neuquén Basin (Argentina) has recently emerged as the main shale oil/gas producer outside USA. The VMF is an extensive world-class hydrocarbon source rock with a prospective area in the order of 30.000 km2. The unit is part of a mixed clastic-carbonate succession deposited in a distally-steepened ramp, characterized by the development of northwest prograding clinoforms. In order to investigate possible relationships between depositional processes, geochemical signature, and geometries, which ultimately impact reservoir production, an integrated study involving inorganic geochemistry, core characterization, and seismic interpretation was conducted along a dip-oriented transect (ca. 25 km) in the center of the Neuquén Basin. The basinal facies are primarily composed of laminated mudstones with the highest content of redox-sensitive elements (V, Mo, Cr, Co, Ni, Zn) depicting sub-horizontal parallel reflections. Toe-of-slope facies comprises mainly laminated and bioturbated mudstones showing a decrease in the amount of redox-sensitive elements coupled with an increment in elements indicative of siliciclastic sedimentation (Si, Al,K, Zr, Ti) and availability of nutrients (Ba, P). Finally, upper slope and roll-over facies involve bioturbated mudstones and mudstones with benthonic foraminifera and are characterized by a relative decrease in elements indicative of siliciclastic sedimentation along with an increase in elements with carbonate affinity (Ca, Sc, P). These results suggest a genetic relationship between inorganic geochemical signature and depositional processes along the clinoform, thus providing and additional proxy to evaluate shale reservoirs particularly in the absence of core and/or 3D seismic data. The Upper Jurassic-Lower Cretaceous Vaca Muerta Formation (VMF) in the Neuquén Basin (Argentina) has recently emerged as the main shale oil/gas producer outside USA. The VMF is an extensive world-class hydrocarbon source rock with a prospective area in the order of 30.000 km². The unit is part of a mixed clastic-carbonate succession deposited in a distally-steepened ramp, characterized by the development of northwest prograding clinoforms. In order to investigate possible relationships between depositional processes, geochemical signature, and geometries, which ultimately impact reservoir production, an integrated study involving inorganic geochemistry, core characterization, and seismic interpretation was conducted along a dip-oriented transect (ca. 25 km) in the center of the Neuquén Basin. The basinal facies are primarily composed of laminated mudstones with the highest content of redox-sensitive elements (V, Mo, Cr, Co, Ni, Zn) depicting sub-horizontal parallel reflections. Toe-of-slope facies comprises mainly laminated and bioturbated mudstones showing a decrease in the amount of redox-sensitive elements coupled with an increment in elements indicative of siliciclastic sedimentation (Si, Al,K, Zr, Ti) and availability of nutrients (Ba, P). Finally, upper slope and roll-over facies involve bioturbated mudstones and mudstones with benthonic foraminifera and are characterized by a relative decrease in elements indicative of siliciclastic sedimentation along with an increase in elements with carbonate affinity (Ca, Sc, P). These results suggest a genetic relationship between inorganic geochemical signature and depositional processes along the clinoform, thus providing and additional proxy to evaluate shale reservoirs particularly in the absence of core and/or 3D seismic data. Panel_15586 Panel_15586 8:05 AM 8:25 AM

The Late Cretaceous Eagle Ford Fm represents marine deposition on the South Texas Shelf during late Cenomanian and Turonian time. The lower Eagle Ford (LEF) is a marl and limestone succession containing elevated %TOC (average TOC ~3.5%, maximum of 6.5%). The upper Eagle Ford (UEF) is a comparatively organic-lean (average TOC ~1%) interval consisting of limestones and marls. A 600-foot-long core containing the Eagle Ford shale was recovered from the Maverick Basin, South Texas. Mineralogical results were generated at a 2-foot interval using X-ray diffraction (XRD), and high-resolution (2-inch sampling interval) chemostratigraphic results were generated using handheld X-ray fluorescence (XRF) unit. The chemostratigraphic record of the Eagle Ford and underlying Buda Fm, supplemented by insights from XRD, TOC, and core description, was evaluated using a hierarchical clustering analysis (HCA) technique in order to (1) quantitatively identify dominant end member geochemical facies compositions, (2) evaluate the chemical facies in terms of their relative elemental rankings, (3) elucidate linkages between lithofacies and chemical facies, and (4) interpret the history of depositional and paleohydrographic conditions during accumulation of the Eagle Ford shale succession. Using a 14-cluster parameterization, HCA identified five dominant clusters that account for 89% of the chemical facies variability in the core. The majority of samples from the Buda Fm, and chemically similar limestones throughout the Eagle Ford succession account for 19% of chemical facies observed, which are best characterized as Mn-enriched limestones. The majority of the UEF limestones account for 26% of the chemical facies identified, which are characterized by enrichments in Sr and U. LEF euxinic marls account for 19% of the chemical facies, and are characterized by enrichments in redox-sensitive trace elements (Mo, V, Ni, Zn, Cu, As, U) and S. This facies also contains the highest %TOC values. Almost 15% of the succession is characterized as oxic marl, with minimal redox-sensitive trace elements, and enrichments in elements associated with siliciclastic detritus (Zr, Al, Ti, K, Rb). Approximately 10% of the succession is characterized as high-Ca oxic marl, with detrital enrichments in Rb, K, and Cr. When integrated with traditional core description, chemical facies provide important insights into vertical and lateral changes in depositional environments and hydrographic conditions in the basin. The Late Cretaceous Eagle Ford Fm represents marine deposition on the South Texas Shelf during late Cenomanian and Turonian time. The lower Eagle Ford (LEF) is a marl and limestone succession containing elevated %TOC (average TOC ~3.5%, maximum of 6.5%). The upper Eagle Ford (UEF) is a comparatively organic-lean (average TOC ~1%) interval consisting of limestones and marls. A 600-foot-long core containing the Eagle Ford shale was recovered from the Maverick Basin, South Texas. Mineralogical results were generated at a 2-foot interval using X-ray diffraction (XRD), and high-resolution (2-inch sampling interval) chemostratigraphic results were generated using handheld X-ray fluorescence (XRF) unit. The chemostratigraphic record of the Eagle Ford and underlying Buda Fm, supplemented by insights from XRD, TOC, and core description, was evaluated using a hierarchical clustering analysis (HCA) technique in order to (1) quantitatively identify dominant end member geochemical facies compositions, (2) evaluate the chemical facies in terms of their relative elemental rankings, (3) elucidate linkages between lithofacies and chemical facies, and (4) interpret the history of depositional and paleohydrographic conditions during accumulation of the Eagle Ford shale succession. Using a 14-cluster parameterization, HCA identified five dominant clusters that account for 89% of the chemical facies variability in the core. The majority of samples from the Buda Fm, and chemically similar limestones throughout the Eagle Ford succession account for 19% of chemical facies observed, which are best characterized as Mn-enriched limestones. The majority of the UEF limestones account for 26% of the chemical facies identified, which are characterized by enrichments in Sr and U. LEF euxinic marls account for 19% of the chemical facies, and are characterized by enrichments in redox-sensitive trace elements (Mo, V, Ni, Zn, Cu, As, U) and S. This facies also contains the highest %TOC values. Almost 15% of the succession is characterized as oxic marl, with minimal redox-sensitive trace elements, and enrichments in elements associated with siliciclastic detritus (Zr, Al, Ti, K, Rb). Approximately 10% of the succession is characterized as high-Ca oxic marl, with detrital enrichments in Rb, K, and Cr. When integrated with traditional core description, chemical facies provide important insights into vertical and lateral changes in depositional environments and hydrographic conditions in the basin. Panel_15520 Panel_15520 8:45 AM 9:05 AM

The lower Jurassic (Liassic) was a time of widespread deposition of organic-rich mudstones, partially oil shales, which are a major source of many hydrocarbon systems in Europe and elsewhere, and also in SW-Germany. The study is focused on the two major black shale intervals in the Liassic in SW-Germany: the early transgressive Psilonoten shale (Hettangian-Sinemurian), which is mostly overlooked as source rock, and the late transgressive Posidonia shale (Toarcian), a well known highly prospective source rock all over Europe and elsewhere. To get a better understanding about the similarities and differences of both oil shales, a detailed source rock study is done based on geochemical and optical kerogen analysis. The focus is on optical analysis of the kerogen composition, preservation and maturation. Optical Kerogen Analysis quantifies the productive versus unproductive proportions of the total kerogen and the oil-prone versus gas-prone kerogen proportions within the productive kerogen of each sample, leading to significantly improved resolution and reliability of kerogen analysis. Analysis of organic matter degradation (microporosity) gives informations on hydrocarbon generation. The integrated optical analysis of organic maturation provides highly reliable information on the maturity of the play. Additional in-situ analysis of microporosity and distribution of organic matter in the Liassic shales is done, based on thin sections and SEM. This interdisciplinary workflow leads to new improved characterization and definition of different types of source rocks and their regional and stratigraphical distribution, providing new detailed insights into the variations of the hydrocarbon potential between early transgressive and late transgressive black shale deposits in the Liassic in SW-Germany, beyond the geochemical data available from previous exploration. Results of the optical based source rock analysis will lead to the definition and characterization of different types of source rocks in the pre-Tertiary of SW-Germany. The lower Jurassic (Liassic) was a time of widespread deposition of organic-rich mudstones, partially oil shales, which are a major source of many hydrocarbon systems in Europe and elsewhere, and also in SW-Germany. The study is focused on the two major black shale intervals in the Liassic in SW-Germany: the early transgressive Psilonoten shale (Hettangian-Sinemurian), which is mostly overlooked as source rock, and the late transgressive Posidonia shale (Toarcian), a well known highly prospective source rock all over Europe and elsewhere. To get a better understanding about the similarities and differences of both oil shales, a detailed source rock study is done based on geochemical and optical kerogen analysis. The focus is on optical analysis of the kerogen composition, preservation and maturation. Optical Kerogen Analysis quantifies the productive versus unproductive proportions of the total kerogen and the oil-prone versus gas-prone kerogen proportions within the productive kerogen of each sample, leading to significantly improved resolution and reliability of kerogen analysis. Analysis of organic matter degradation (microporosity) gives informations on hydrocarbon generation. The integrated optical analysis of organic maturation provides highly reliable information on the maturity of the play. Additional in-situ analysis of microporosity and distribution of organic matter in the Liassic shales is done, based on thin sections and SEM. This interdisciplinary workflow leads to new improved characterization and definition of different types of source rocks and their regional and stratigraphical distribution, providing new detailed insights into the variations of the hydrocarbon potential between early transgressive and late transgressive black shale deposits in the Liassic in SW-Germany, beyond the geochemical data available from previous exploration. Results of the optical based source rock analysis will lead to the definition and characterization of different types of source rocks in the pre-Tertiary of SW-Germany. Panel_15522 Panel_15522 9:05 AM 9:25 AM

Panel_15811 Panel_15811 9:25 AM 12:00 AM

Organic-richness in shale is controlled by the interplay between the three factors viz., organic productivity, preservation and dilution. This study is focused on identifying the effect of these factors in the context of upper and lower (U&L) Bakken shales in the Williston basin. Lithologically, the U&L shales are siliceous mudstones with the Total Organic Carbon (TOC) varying between 3 to 20 weight percent. X-ray fluorescence results, TOC information, X-ray diffraction mineralogy and stable isotope data (C, O and S) collected from 10 well cores are used to determine the influence of detrital sediment influx, paleoproductivity and paleoceanographic conditions in controlling organic content in the U&L shales. The mineralogical composition of the U&L shales may vary as follows: 30-45% of biogenic, detrital and authigenic quartz silt, 20- 30% clay, 5-10% feldspar, 2-11% detrital and authigenic dolomite and 3-9% pyrite. So, to distinguish biogenic silica-rich intervals from detrital sediment-rich intervals, inorganic geochemical proxies (Si/Ti and Al/Ti ratios) are used. The vertical profiles show positive covariance between TOC-rich and the detrital sediment-rich intervals, which demonstrate the beneficial effect of detrital sediment input in the organic matter (OM) accumulation. Therefore, an optimum sedimentation rate instead of creating a dilution effect, appears to have helped in quick preservation of OM. Paleoproductivity and paleonutrient utilization was determined by using stable Nitrogen isotope data as a proxy. In U&L shales, the covariance between lighter values of deltaN15 and higher TOC reveals that OM accumulation relies on increased nutrient supply for a higher organic productivity. The nutrients required to sustain the organic productivity was supplied by the detrital sediment influx and the surface water currents within the basin. Anoxic-euxinic basin condition results in higher preservation of OM. Enrichment of redox-sensitive trace elements (like Mo, V, U, Ni and Cu) and their relation with TOC, values of C/S ratio and degree of pyritization suggests that the Bakken shales were deposited in an anoxic-euxinic basin with higher OM preservation potential. Therefore this study concludes that higher paleoproductivity driven by critical nutrient supply, optimum detrital sedimentation rate and anoxic-euxinic basin condition resulted in higher accumulation and better preservation of the OM within the Bakken shales. Organic-richness in shale is controlled by the interplay between the three factors viz., organic productivity, preservation and dilution. This study is focused on identifying the effect of these factors in the context of upper and lower (U&L) Bakken shales in the Williston basin. Lithologically, the U&L shales are siliceous mudstones with the Total Organic Carbon (TOC) varying between 3 to 20 weight percent. X-ray fluorescence results, TOC information, X-ray diffraction mineralogy and stable isotope data (C, O and S) collected from 10 well cores are used to determine the influence of detrital sediment influx, paleoproductivity and paleoceanographic conditions in controlling organic content in the U&L shales. The mineralogical composition of the U&L shales may vary as follows: 30-45% of biogenic, detrital and authigenic quartz silt, 20- 30% clay, 5-10% feldspar, 2-11% detrital and authigenic dolomite and 3-9% pyrite. So, to distinguish biogenic silica-rich intervals from detrital sediment-rich intervals, inorganic geochemical proxies (Si/Ti and Al/Ti ratios) are used. The vertical profiles show positive covariance between TOC-rich and the detrital sediment-rich intervals, which demonstrate the beneficial effect of detrital sediment input in the organic matter (OM) accumulation. Therefore, an optimum sedimentation rate instead of creating a dilution effect, appears to have helped in quick preservation of OM. Paleoproductivity and paleonutrient utilization was determined by using stable Nitrogen isotope data as a proxy. In U&L shales, the covariance between lighter values of deltaN15 and higher TOC reveals that OM accumulation relies on increased nutrient supply for a higher organic productivity. The nutrients required to sustain the organic productivity was supplied by the detrital sediment influx and the surface water currents within the basin. Anoxic-euxinic basin condition results in higher preservation of OM. Enrichment of redox-sensitive trace elements (like Mo, V, U, Ni and Cu) and their relation with TOC, values of C/S ratio and degree of pyritization suggests that the Bakken shales were deposited in an anoxic-euxinic basin with higher OM preservation potential. Therefore this study concludes that higher paleoproductivity driven by critical nutrient supply, optimum detrital sedimentation rate and anoxic-euxinic basin condition resulted in higher accumulation and better preservation of the OM within the Bakken shales. Panel_15517 Panel_15517 10:10 AM 10:30 AM

Marine diatoms deposit biogenic silica as amorphous opal-A. These deposits interact with saturating aqueous solutions, transforming to microcrystalline opal-CT and eventually quartz through a series of dissolution and precipitation reactions. The mineralogical changes cause corresponding changes in rock properties such as porosity, permeability, and acoustic response. The enhanced permeability and preserved porosity during these transitions may result in formation of diagenetic hydrocarbon traps. Successful exploitation of diagenetic traps in oil and gas exploration requires an understanding of how quickly these phase transitions occur and how natural variations in rock composition affect the transition rates. In this study, the kinetics of the opal-A to opal-CT phase transition were determined through a series of hydrous pyrolysis experiments. Two diatomite samples from the Miocene Monterey Formation, California, were used, both from the same pedogenic weathering profile. The samples each comprise approximately 80 wt% opal-A, 10 wt% phyllosilicates, and 6 wt% quartz. However, they have different amounts of TOC (0.36 wt% and 4.65 wt%) and contain a thermally mature Type II kerogen. The samples were mixed with a buffered aqueous solution that ensured the fluid maintained pH 7 or greater, and the mixtures were pyrolyzed at multiple temperatures between 280°C and 330°C. The pyrolysis experiments sampled the transition from opal-A to opal-CT and showed that the conversion in the high-TOC sample was significantly delayed compared to the low-TOC sample at the same temperature. Data at multiple temperatures were combined to determine the activation energy and pre-exponential factor for the conversion of each of the two samples. These kinetics data, combined with knowledge of the local thermal history, allow prediction of the opal-A to opal-CT transition depth in a basin. The estimated transition depth can then be used to predict diagenetic trap locations or identify mineralogical sources of cross-cutting reflectors in seismic data. Low-TOC kinetics provide a baseline for these estimates, whereas high-TOC kinetics demonstrate the extent to which organic material affects the reaction rate in source rocks. Marine diatoms deposit biogenic silica as amorphous opal-A. These deposits interact with saturating aqueous solutions, transforming to microcrystalline opal-CT and eventually quartz through a series of dissolution and precipitation reactions. The mineralogical changes cause corresponding changes in rock properties such as porosity, permeability, and acoustic response. The enhanced permeability and preserved porosity during these transitions may result in formation of diagenetic hydrocarbon traps. Successful exploitation of diagenetic traps in oil and gas exploration requires an understanding of how quickly these phase transitions occur and how natural variations in rock composition affect the transition rates. In this study, the kinetics of the opal-A to opal-CT phase transition were determined through a series of hydrous pyrolysis experiments. Two diatomite samples from the Miocene Monterey Formation, California, were used, both from the same pedogenic weathering profile. The samples each comprise approximately 80 wt% opal-A, 10 wt% phyllosilicates, and 6 wt% quartz. However, they have different amounts of TOC (0.36 wt% and 4.65 wt%) and contain a thermally mature Type II kerogen. The samples were mixed with a buffered aqueous solution that ensured the fluid maintained pH 7 or greater, and the mixtures were pyrolyzed at multiple temperatures between 280°C and 330°C. The pyrolysis experiments sampled the transition from opal-A to opal-CT and showed that the conversion in the high-TOC sample was significantly delayed compared to the low-TOC sample at the same temperature. Data at multiple temperatures were combined to determine the activation energy and pre-exponential factor for the conversion of each of the two samples. These kinetics data, combined with knowledge of the local thermal history, allow prediction of the opal-A to opal-CT transition depth in a basin. The estimated transition depth can then be used to predict diagenetic trap locations or identify mineralogical sources of cross-cutting reflectors in seismic data. Low-TOC kinetics provide a baseline for these estimates, whereas high-TOC kinetics demonstrate the extent to which organic material affects the reaction rate in source rocks. Panel_15518 Panel_15518 10:30 AM 10:50 AM

A comparative chemostratigraphic analysis of a Marcellus Shale core from southwestern Pennsylvania and a Utica Shale core recovered from eastern New York using handheld XRF technology reveals significant differences in the concentration of elements that serve as proxies of detrital flux and redox conditions. Perhaps the most noticeable differences between the Marcellus and Utica is reflected in the abundances of Al, a robust proxy for clay content, and redox-sensitive elements, U and Mo, both of which are especially useful to the analysis of oxygen-deficient marine systems. Though enrichment of Mo and U in marine deposits can be ascribed to the authigenic uptake from seawater enhanced by oxygen deficient conditions, authigenic enrichment mechanisms of both elements differ from each other. The Marcellus succession illustrates a general increase of Al upsection from the TST through the RST deposits. No such trends are observed in the Utica Shale as Al remains generally consistent throughout the most organic-rich intervals. Overall, Al is higher in the Marcellus relative to the Utica suggesting higher clay content in the former. Impressed upon the generally increasing clastic input of the Marcellus are marked redox variations indicated by U and Mo enrichment that tell of increasingly reducing environmental conditions. These data reflect sediment accumulation in an “unrestricted marine” environment setting in which the supply of Mo to the water column was renewed at a rate that exceeded its rate of sequestration in sulfidic sediment. The concentration of redox proxies in the Utica Shale core is much less than one might expect of an organic-rich black shale. Both Mo and U values are suppressed throughout much of the core and only minimally enriched within the organic-rich sections. Chemostratigraphic analysis of the Utica core suggests that the organic-rich deposits accumulated under anoxic to intermittently euxinic conditions that would have favored the authigenic uptake of U and Mo. However, the depleted nature of the most organic-rich deposits of the Utica Shale reflect major differences between Ordovician and Devonian worlds, possibly the result of global anoxia and consequent drawdown of the global U and Mo inventory and lack of an established land plant root system that would have favored the development of clay soil profiles. A comparative chemostratigraphic analysis of a Marcellus Shale core from southwestern Pennsylvania and a Utica Shale core recovered from eastern New York using handheld XRF technology reveals significant differences in the concentration of elements that serve as proxies of detrital flux and redox conditions. Perhaps the most noticeable differences between the Marcellus and Utica is reflected in the abundances of Al, a robust proxy for clay content, and redox-sensitive elements, U and Mo, both of which are especially useful to the analysis of oxygen-deficient marine systems. Though enrichment of Mo and U in marine deposits can be ascribed to the authigenic uptake from seawater enhanced by oxygen deficient conditions, authigenic enrichment mechanisms of both elements differ from each other. The Marcellus succession illustrates a general increase of Al upsection from the TST through the RST deposits. No such trends are observed in the Utica Shale as Al remains generally consistent throughout the most organic-rich intervals. Overall, Al is higher in the Marcellus relative to the Utica suggesting higher clay content in the former. Impressed upon the generally increasing clastic input of the Marcellus are marked redox variations indicated by U and Mo enrichment that tell of increasingly reducing environmental conditions. These data reflect sediment accumulation in an “unrestricted marine” environment setting in which the supply of Mo to the water column was renewed at a rate that exceeded its rate of sequestration in sulfidic sediment. The concentration of redox proxies in the Utica Shale core is much less than one might expect of an organic-rich black shale. Both Mo and U values are suppressed throughout much of the core and only minimally enriched within the organic-rich sections. Chemostratigraphic analysis of the Utica core suggests that the organic-rich deposits accumulated under anoxic to intermittently euxinic conditions that would have favored the authigenic uptake of U and Mo. However, the depleted nature of the most organic-rich deposits of the Utica Shale reflect major differences between Ordovician and Devonian worlds, possibly the result of global anoxia and consequent drawdown of the global U and Mo inventory and lack of an established land plant root system that would have favored the development of clay soil profiles. Panel_15525 Panel_15525 10:50 AM 11:10 AM

An evaluation of selected source rocks from the Mississippian marine Banff-Exshaw or Bakken and Triassic Montney/Doig formations from Alberta (Western Canada) and the Mississippian lacustrine Horton Group shale sequences from New Brunswick (Eastern Canada) were evaluated based on the issue of maturity or facies dependency of methane adsorptions, the changes in primary or secondary organic pores in shale, and primary migration of oil within various kerogen network. The amount of adsorbed and free liquids or gases and primary migration of oil within kerogen network is related to the changes of organic facies (labile versus inert) and organic maturity (oil or gas phase). This data illustrates a close relationship with the neoformed liquid hydrocarbons, change in the proportion of adsorbed and free oil and gases, and the changes in kerogen network within various shale plays. The selected adsorption and desorption capabilities in selected kerogen Type I, II, II-III shale and carbonate source rocks indicate the possible presence of parallel gas and liquid adsorptions within the labile phases in different phases of advanced maturity. They show changes in both primary and secondary pores within the organic matter of various kerogen types. This data also suggests the possible implications of multiplayer adsorptions where adsorptions are pressure and temperature dependant. The maturation time sequences of oil and gas adsorptions within various macerals (organoclasts) species change to free oil or gas phases. This process also defines the timing and volumetric changes of primary versus secondary pores in various macerals in shale. This data may also define the path of oil migration within the maceral pore structure for enhanced production within shale. An evaluation of selected source rocks from the Mississippian marine Banff-Exshaw or Bakken and Triassic Montney/Doig formations from Alberta (Western Canada) and the Mississippian lacustrine Horton Group shale sequences from New Brunswick (Eastern Canada) were evaluated based on the issue of maturity or facies dependency of methane adsorptions, the changes in primary or secondary organic pores in shale, and primary migration of oil within various kerogen network. The amount of adsorbed and free liquids or gases and primary migration of oil within kerogen network is related to the changes of organic facies (labile versus inert) and organic maturity (oil or gas phase). This data illustrates a close relationship with the neoformed liquid hydrocarbons, change in the proportion of adsorbed and free oil and gases, and the changes in kerogen network within various shale plays. The selected adsorption and desorption capabilities in selected kerogen Type I, II, II-III shale and carbonate source rocks indicate the possible presence of parallel gas and liquid adsorptions within the labile phases in different phases of advanced maturity. They show changes in both primary and secondary pores within the organic matter of various kerogen types. This data also suggests the possible implications of multiplayer adsorptions where adsorptions are pressure and temperature dependant. The maturation time sequences of oil and gas adsorptions within various macerals (organoclasts) species change to free oil or gas phases. This process also defines the timing and volumetric changes of primary versus secondary pores in various macerals in shale. This data may also define the path of oil migration within the maceral pore structure for enhanced production within shale. Panel_15524 Panel_15524 11:10 AM 11:30 AM

The organic petrography of shale samples (n=20) from the Upper Permian Lucaogou Formation, NW China, was used to evaluate the nature of organic matter (OM) in the context of an evolving lake system. The samples were widely spaced over a ~200 m cored section, and included 1) organic-rich intervals from the underfilled lake portion (lower stratigraphic interval) of the formation, and 2) organic-lean intervals, including siltstones, in the overlying balanced-filled lake portion. OM is dominated by moderate to strongly fluorescent amorphous algal(?) material that occurs in a continuum from lamellar stringers, 10-20 µm thick, up to >1 mm in length (microbial mat?) to a finely-disseminated organic groundmass intimately intermixed with mineral matrix. The organic groundmass may derive from multiple pathways, including: 1) original submicroscopic OM (e.g., algae), 2) mechanical and chemical breakdown of larger unicellular algal bodies (telalginite) and lamalginite (microbial mat?), and 3) bacterial biomass products. A unicellular prasinophyte green alga(?), similar to Tasmanites in marine rocks, is present as discrete flattened discs 50-100 µm in diameter. The abundance of Type I OM is consistent with a lacustrine origin for the Lucaogou, and strong fluorescence indicates that OM has undergone limited thermal maturation. Type III OM including vitrinite and inertinite also is abundant. Some vitrinite with remnant structure and reddish internal reflections has low-moderate fluorescence, indicating an atypical H-rich composition. Solid bitumen fills pores and occurs throughout the entire stratigraphic interval in a wide range of morphology, reflectance, and fluorescence intensity. A discrete bitumen population with low reflectance (0.26-0.36% +/- 0.04-0.09) is interpreted as an early-hydrocarbon generation product. Vitrinite is difficult to conclusively discriminate from high-reflecting solid bitumen and low-reflecting inertinite because their reflectance values overlap with vitrinite. Nevertheless, vitrinite reflectance values were relatively low at 0.47-0.58% (+/- 0.04-0.07), and although consistent with some fluorescence data, the measured Ro values are low relative to other thermal maturity indicators. Qualitatively, microbial mat(?) is present or better preserved in the underfilled portion of the lake, whereas other macerals generally are present consistently throughout the section. The organic petrography of shale samples (n=20) from the Upper Permian Lucaogou Formation, NW China, was used to evaluate the nature of organic matter (OM) in the context of an evolving lake system. The samples were widely spaced over a ~200 m cored section, and included 1) organic-rich intervals from the underfilled lake portion (lower stratigraphic interval) of the formation, and 2) organic-lean intervals, including siltstones, in the overlying balanced-filled lake portion. OM is dominated by moderate to strongly fluorescent amorphous algal(?) material that occurs in a continuum from lamellar stringers, 10-20 µm thick, up to >1 mm in length (microbial mat?) to a finely-disseminated organic groundmass intimately intermixed with mineral matrix. The organic groundmass may derive from multiple pathways, including: 1) original submicroscopic OM (e.g., algae), 2) mechanical and chemical breakdown of larger unicellular algal bodies (telalginite) and lamalginite (microbial mat?), and 3) bacterial biomass products. A unicellular prasinophyte green alga(?), similar to Tasmanites in marine rocks, is present as discrete flattened discs 50-100 µm in diameter. The abundance of Type I OM is consistent with a lacustrine origin for the Lucaogou, and strong fluorescence indicates that OM has undergone limited thermal maturation. Type III OM including vitrinite and inertinite also is abundant. Some vitrinite with remnant structure and reddish internal reflections has low-moderate fluorescence, indicating an atypical H-rich composition. Solid bitumen fills pores and occurs throughout the entire stratigraphic interval in a wide range of morphology, reflectance, and fluorescence intensity. A discrete bitumen population with low reflectance (0.26-0.36% +/- 0.04-0.09) is interpreted as an early-hydrocarbon generation product. Vitrinite is difficult to conclusively discriminate from high-reflecting solid bitumen and low-reflecting inertinite because their reflectance values overlap with vitrinite. Nevertheless, vitrinite reflectance values were relatively low at 0.47-0.58% (+/- 0.04-0.07), and although consistent with some fluorescence data, the measured Ro values are low relative to other thermal maturity indicators. Qualitatively, microbial mat(?) is present or better preserved in the underfilled portion of the lake, whereas other macerals generally are present consistently throughout the section. Panel_15519 Panel_15519 11:30 AM 11:50 AM

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Panel_14432 Panel_14432 8:00 AM 11:50 AM

Panel_15812 Panel_15812 8:00 AM 12:00 AM

The Niobrara is a structurally complex reservoir that requires a multi-disciplined geosteering approach to achieve optimum well placement and maximize return on investment. A successful well plan strikes a balanced approach that not only incorporates the geologic goals of the well, but also takes into consideration factors that affect the operational efficiencies of both the drilling and the stimulation. When Whiting entered the Niobrara play, our geosteering was based primarily on gamma LWD logs. While this approach was somewhat effective, it became evident that the wellbores were not maximizing contact with the most brittle Niobrara chalk layers. As a consequence, Whiting’s geosteering philosophy evolved from a passive or “reactive” gamma-based methodology to a proactive “forward-looking” approach to geosteering. Anticipation of, rather than reaction to, structural features would be critical for success. Whiting was able to make this shift in geosteering philosophy, due to the acquisition and interpretation of over 700 square miles of 3D seismic data. A detailed review of early wells using the new 3D seismic volume yielded several compelling observations. Primarily, it exposed an under appreciation of localized structural complexity internal to the Niobrara and an overreliance on regional structure as a guide to geosteering. The structure was much more complex than initially thought, with numerous narrow graben features with highly diverse orientations presenting new challenges for each drilling-spacing unit. A secondary observation was that wells which had the greatest number of frac stages placed in the clean chalk facies had the best individual well performance. Conversely, wells spending a significant amount of vertical section in the marls generally performed more poorly. This trend is likely due to the reduced efficiency of the stimulations in stages that were placed in the more ductile, bentonite-rich facies of the Niobrara. Whiting’s current geosteering strategy utilizes a series of TVD and VS waypoints to give a best-fit wellbore path based on 3D seismic interpretation, facies mapping, offset well data and optimum drilling parameters. Narrow grabens are “speared through” without inducing excess wellbore tortuosity. These factors must be considered when employing an active geosteering strategy in a structurally complex unconventional reservoir. The Niobrara is a structurally complex reservoir that requires a multi-disciplined geosteering approach to achieve optimum well placement and maximize return on investment. A successful well plan strikes a balanced approach that not only incorporates the geologic goals of the well, but also takes into consideration factors that affect the operational efficiencies of both the drilling and the stimulation. When Whiting entered the Niobrara play, our geosteering was based primarily on gamma LWD logs. While this approach was somewhat effective, it became evident that the wellbores were not maximizing contact with the most brittle Niobrara chalk layers. As a consequence, Whiting’s geosteering philosophy evolved from a passive or “reactive” gamma-based methodology to a proactive “forward-looking” approach to geosteering. Anticipation of, rather than reaction to, structural features would be critical for success. Whiting was able to make this shift in geosteering philosophy, due to the acquisition and interpretation of over 700 square miles of 3D seismic data. A detailed review of early wells using the new 3D seismic volume yielded several compelling observations. Primarily, it exposed an under appreciation of localized structural complexity internal to the Niobrara and an overreliance on regional structure as a guide to geosteering. The structure was much more complex than initially thought, with numerous narrow graben features with highly diverse orientations presenting new challenges for each drilling-spacing unit. A secondary observation was that wells which had the greatest number of frac stages placed in the clean chalk facies had the best individual well performance. Conversely, wells spending a significant amount of vertical section in the marls generally performed more poorly. This trend is likely due to the reduced efficiency of the stimulations in stages that were placed in the more ductile, bentonite-rich facies of the Niobrara. Whiting’s current geosteering strategy utilizes a series of TVD and VS waypoints to give a best-fit wellbore path based on 3D seismic interpretation, facies mapping, offset well data and optimum drilling parameters. Narrow grabens are “speared through” without inducing excess wellbore tortuosity. These factors must be considered when employing an active geosteering strategy in a structurally complex unconventional reservoir. Panel_14981 Panel_14981 8:05 AM 8:25 AM

Log evaluation of the clastic and carbonate lithologies in the Green River and upper Wasatch formations of the Uinta basin is complicated by the complex mineralogy and thin interbedding of diverse rock types. Simple zoned models smooth out these differences to yield porosities and saturations that may on average be correct, but misleading on a bed-by-bed basis. Probabilistic or stochastic approaches have been advocated for this area, but suffer from a lack of transparency, require specialized software and expert users, and require advanced logging measurements such as elemental capture spectroscopy logs to solve the problem. Although appropriate for an operator with a large formation evaluation budget and full access to all logging data run in a well, probabilistic methods do not work as well with public domain data or for mapping large areas with incomplete competitor data. We present a simple, deterministic 4-mineral solution consisting of quartz, calcite, dolomite, and “mixed clay” without attempting to derive the minor mineral components or individual clay species. The solution only requires the four basic logging measurements that are widely available: gamma ray, density, neutron porosity, and Pe. The solution does require one significant simplifying assumption: there is no dolomite in the shaly fraction of the interval; it only exists in the clean formation fraction. We then solve two triangles in apparent matrix density (RHOMAA) – apparent photoelectric cross-section (UMAA) space: 1) for clean (non-shaly) rocks the quartz-calcite-dolomite triangle; and 2) for shaly rocks, the quartz-calcite-clay triangle. These are solved using a gamma ray filter to separate clean from shaly formation solutions followed by a matrix inversion approach of 3 linear equations for each branch. The results are re-normalized to sum to 1 without any negative components, and are filtered for bad hole or other adverse logging conditions. The proposed approach yields lithology solutions very similar to logging vendor supplied multi-mineral solutions in terms of bulk mineralogy. Mineral endpoints are easily adjusted by the user as the “quartz point” drifts in rocks with high feldspar contents, or if the clay point drifts regionally. Organic matter and in many cases pyrite can also be determined in a subsequent step. The method can be implemented in a general purpose software package (e.g. Petra, GeoGraphix) or in Excel. Log evaluation of the clastic and carbonate lithologies in the Green River and upper Wasatch formations of the Uinta basin is complicated by the complex mineralogy and thin interbedding of diverse rock types. Simple zoned models smooth out these differences to yield porosities and saturations that may on average be correct, but misleading on a bed-by-bed basis. Probabilistic or stochastic approaches have been advocated for this area, but suffer from a lack of transparency, require specialized software and expert users, and require advanced logging measurements such as elemental capture spectroscopy logs to solve the problem. Although appropriate for an operator with a large formation evaluation budget and full access to all logging data run in a well, probabilistic methods do not work as well with public domain data or for mapping large areas with incomplete competitor data. We present a simple, deterministic 4-mineral solution consisting of quartz, calcite, dolomite, and “mixed clay” without attempting to derive the minor mineral components or individual clay species. The solution only requires the four basic logging measurements that are widely available: gamma ray, density, neutron porosity, and Pe. The solution does require one significant simplifying assumption: there is no dolomite in the shaly fraction of the interval; it only exists in the clean formation fraction. We then solve two triangles in apparent matrix density (RHOMAA) – apparent photoelectric cross-section (UMAA) space: 1) for clean (non-shaly) rocks the quartz-calcite-dolomite triangle; and 2) for shaly rocks, the quartz-calcite-clay triangle. These are solved using a gamma ray filter to separate clean from shaly formation solutions followed by a matrix inversion approach of 3 linear equations for each branch. The results are re-normalized to sum to 1 without any negative components, and are filtered for bad hole or other adverse logging conditions. The proposed approach yields lithology solutions very similar to logging vendor supplied multi-mineral solutions in terms of bulk mineralogy. Mineral endpoints are easily adjusted by the user as the “quartz point” drifts in rocks with high feldspar contents, or if the clay point drifts regionally. Organic matter and in many cases pyrite can also be determined in a subsequent step. The method can be implemented in a general purpose software package (e.g. Petra, GeoGraphix) or in Excel. Panel_14980 Panel_14980 8:25 AM 8:45 AM

The Codell Sandstone has recently been the subject of extensive exploration and subsequent development activity in both the Colorado and Wyoming portions of northern DJ Basin. The Niobrara Formation has been the primary historical exploration target since the late 1980’s due to success at the Silo Field from horizontal wells drilled in the Niobrara B Bench. In 2009, EOG Resources discovered the Hereford Field with the Jake 02-01H, producing approximately 1700 barrels of oil per day initially from the Niobrara B Bench. The next two years in the area saw much drilling focused for the Niobrara B Bench with the completion of many non-commercial wells. In 2011, SM Energy drilled a lateral focused on evaluating the Codell Sandstone. Cirque Resources, Kaiser Francis and EOG soon followed with their own exploratory wells, establishing the play. This new play area is thermally in the oil window. Codell Sandstone oil producers have gas-oil ratios less than 2000 scf/bbl. The Codell Sandstone thins from north to south due to erosional truncation beneath an angular unconformity at the base of the Fort Hays Limestone Member of the Niobrara Formation. Gross thickness ranges from 18 to 33 feet. The Codell Sandstone is a very-fine to fine-grained sandstone and produces oil from two main facies: bioturbated sandstone and laminated sandstone. The laminated facies is parallel to sub-horizontally bedded, has 8 to 15 percent porosity, and .01 to 0.10 millidarcies permeability. The bioturbated sandstone has 8 to 13 percent porosity and .008 to .05 millidarcies permeability. The Codell Sandstone is a low-resistivity pay zone that produces oil with low water cuts from zones with less than 10 ohm-m resistivity. Clay content is 15–25% with abundant microporosity as imaged with epifluorescent microscopy, accounting for high bound water content and explaining the low formation resistivity. Oil typing indicates the oil found in the Codell is sourced from the Niobrara and is distributed across the area through migration. Oil saturation varies across the play depending the on the distance from areas of oil generation and expulsion into the Codell. The Codell Sandstone has recently been the subject of extensive exploration and subsequent development activity in both the Colorado and Wyoming portions of northern DJ Basin. The Niobrara Formation has been the primary historical exploration target since the late 1980’s due to success at the Silo Field from horizontal wells drilled in the Niobrara B Bench. In 2009, EOG Resources discovered the Hereford Field with the Jake 02-01H, producing approximately 1700 barrels of oil per day initially from the Niobrara B Bench. The next two years in the area saw much drilling focused for the Niobrara B Bench with the completion of many non-commercial wells. In 2011, SM Energy drilled a lateral focused on evaluating the Codell Sandstone. Cirque Resources, Kaiser Francis and EOG soon followed with their own exploratory wells, establishing the play. This new play area is thermally in the oil window. Codell Sandstone oil producers have gas-oil ratios less than 2000 scf/bbl. The Codell Sandstone thins from north to south due to erosional truncation beneath an angular unconformity at the base of the Fort Hays Limestone Member of the Niobrara Formation. Gross thickness ranges from 18 to 33 feet. The Codell Sandstone is a very-fine to fine-grained sandstone and produces oil from two main facies: bioturbated sandstone and laminated sandstone. The laminated facies is parallel to sub-horizontally bedded, has 8 to 15 percent porosity, and .01 to 0.10 millidarcies permeability. The bioturbated sandstone has 8 to 13 percent porosity and .008 to .05 millidarcies permeability. The Codell Sandstone is a low-resistivity pay zone that produces oil with low water cuts from zones with less than 10 ohm-m resistivity. Clay content is 15–25% with abundant microporosity as imaged with epifluorescent microscopy, accounting for high bound water content and explaining the low formation resistivity. Oil typing indicates the oil found in the Codell is sourced from the Niobrara and is distributed across the area through migration. Oil saturation varies across the play depending the on the distance from areas of oil generation and expulsion into the Codell. Panel_14988 Panel_14988 8:45 AM 9:05 AM

Deposition of the Devonian-Mississippian Sappington Fm. is contemporaneous with the Bakken Fm. in the Williston Basin. Despite good drilling success rates, hydrocarbon production rates across the Williston Basin are highly variable and at present, many of the geologic controls behind this heterogeneity are poorly understood. The Sappington Fm. in the Bridger Range (BR), MT offers an opportunity to study the architecture and facies heterogeneity of Bakken-equivalent strata at the surface. Here we present results from an outcrop study along a 17 km transect in the BR to discern the lateral lithologic heterogeneity and architecture on the reservoir and field scale. The Sappington Fm. is divided into three members: the lower and upper organic-rich shale members and a middle calcareous, siltstone to very fine-grained sandstone member. Facies in the lower and upper shale members include: organic-rich mudstones; muddy, organic-rich siltstones; and silty, bioturbated, organic-rich mudstones. These members are interpreted as being deposited in a dysoxic (anoxic?), semi-restricted offshore environment. Middle Sappington member facies include cross-stratified and rippled sandstones, and bioturbated sandstones and siltstones. Normal-marine assemblages of Cruziana ichnofauna and cross- and ripple-stratification suggest deposition in a normal-marine shoreface environment. The Sappington Fm. thickens from 16 m in the south to 23 m in the northern BR. Lithofacies relationships change laterally across the BR and contribute to a complex stratigraphic architecture. The middle member of the Sappington Fm. in the southern BR displays more proximal facies with larger, planar, and high angle cross-stratified bedforms and the highest abundance of the coarsest grained sand in the system. In the northern BR, facies of the middle Sappington member contain smaller ripple lamination and are more heavily bioturbated. Conversely, the upper and lower shales thin in a southerly direction and spectral GR data suggests a lower organic content in the southern locations. The facies distribution and thickening trends, combined with paleoflow analysis, suggest Sappington Fm. shoreface deposition in the BR, with sediment transport directed in a northerly direction. Heterogeneity of facies and architecture of sedimentary elements observed along this depositional dip section provide insight into the geologic controls of reservoirs and the fate of preserved organic carbon on a development scale. Deposition of the Devonian-Mississippian Sappington Fm. is contemporaneous with the Bakken Fm. in the Williston Basin. Despite good drilling success rates, hydrocarbon production rates across the Williston Basin are highly variable and at present, many of the geologic controls behind this heterogeneity are poorly understood. The Sappington Fm. in the Bridger Range (BR), MT offers an opportunity to study the architecture and facies heterogeneity of Bakken-equivalent strata at the surface. Here we present results from an outcrop study along a 17 km transect in the BR to discern the lateral lithologic heterogeneity and architecture on the reservoir and field scale. The Sappington Fm. is divided into three members: the lower and upper organic-rich shale members and a middle calcareous, siltstone to very fine-grained sandstone member. Facies in the lower and upper shale members include: organic-rich mudstones; muddy, organic-rich siltstones; and silty, bioturbated, organic-rich mudstones. These members are interpreted as being deposited in a dysoxic (anoxic?), semi-restricted offshore environment. Middle Sappington member facies include cross-stratified and rippled sandstones, and bioturbated sandstones and siltstones. Normal-marine assemblages of Cruziana ichnofauna and cross- and ripple-stratification suggest deposition in a normal-marine shoreface environment. The Sappington Fm. thickens from 16 m in the south to 23 m in the northern BR. Lithofacies relationships change laterally across the BR and contribute to a complex stratigraphic architecture. The middle member of the Sappington Fm. in the southern BR displays more proximal facies with larger, planar, and high angle cross-stratified bedforms and the highest abundance of the coarsest grained sand in the system. In the northern BR, facies of the middle Sappington member contain smaller ripple lamination and are more heavily bioturbated. Conversely, the upper and lower shales thin in a southerly direction and spectral GR data suggests a lower organic content in the southern locations. The facies distribution and thickening trends, combined with paleoflow analysis, suggest Sappington Fm. shoreface deposition in the BR, with sediment transport directed in a northerly direction. Heterogeneity of facies and architecture of sedimentary elements observed along this depositional dip section provide insight into the geologic controls of reservoirs and the fate of preserved organic carbon on a development scale. Panel_14985 Panel_14985 9:05 AM 9:25 AM

Panel_15732 Panel_15732 9:25 AM 12:00 AM

The Upper Cretaceous Second White Specks petroleum system is actively being explored as an emerging shale oil resource play across western Alberta. Historically, several highly productive vertical oil wells (+1 million barrels) testify the prolific character of the Second White Specks petroleum system, although often dismissed as an unpredictable fracture controlled play based on poor production in offsetting wells. This study reveals complex stratal architectures comprised of 14 parasequences, each with mappable facies assemblages that characterize these heterolithic mudstone deposits. Sequence stratigraphic and sedimentological facies relationships highlight a series of stacked and intercalated mudstone units comprised of organic, siliciclastic and calcareous sediments largely from locally sourced organic and pelagic fall-out as well as detrital sediments from western and eastern localities. Lateral distribution of sedimentary facies units therefore defines potential reservoir fairways, the foundation for subsequent play fairway characterization. Regional cross sections using 296 well logs across an area, T35-45, R3W5-9W5, established a sequence stratigraphic framework to evaluate parasequence stacking patterns. 10 cores and 27 petrographic samples help define facies assemblages within the succession. Identifying lateral and vertical variations in sedimentary facies is illustrated by facies isopach maps, complemented by facies distribution maps. These reflect petrophysical facies distributions that correlate to facies described in core and thin section samples. Depositionally, sedimentary bedforms (current ripples, graded beds, bioclastic debris layers) documents a depositional setting immediately below or above storm wave base, with deposition from a wide range of traction currents. This suggests deposition in a relatively high energy, shallow water setting, supporting the interpretation of stacked shelf deposits comprising the Second White Specks petroleum system. In addition, analysis of pore size distribution data across the succession provides insights into pore throat morphologies that can be tied to facies distributions. Pore sizes occur as micro-, meso- and macropores (vol %), typically linked to interparticle and grain dissolution, providing insight into storage and flow characteristics for each facies. Collectively, this helps to identify various light oil fairways to be exploited by multistage hydraulically fractured horizontal wells. The Upper Cretaceous Second White Specks petroleum system is actively being explored as an emerging shale oil resource play across western Alberta. Historically, several highly productive vertical oil wells (+1 million barrels) testify the prolific character of the Second White Specks petroleum system, although often dismissed as an unpredictable fracture controlled play based on poor production in offsetting wells. This study reveals complex stratal architectures comprised of 14 parasequences, each with mappable facies assemblages that characterize these heterolithic mudstone deposits. Sequence stratigraphic and sedimentological facies relationships highlight a series of stacked and intercalated mudstone units comprised of organic, siliciclastic and calcareous sediments largely from locally sourced organic and pelagic fall-out as well as detrital sediments from western and eastern localities. Lateral distribution of sedimentary facies units therefore defines potential reservoir fairways, the foundation for subsequent play fairway characterization. Regional cross sections using 296 well logs across an area, T35-45, R3W5-9W5, established a sequence stratigraphic framework to evaluate parasequence stacking patterns. 10 cores and 27 petrographic samples help define facies assemblages within the succession. Identifying lateral and vertical variations in sedimentary facies is illustrated by facies isopach maps, complemented by facies distribution maps. These reflect petrophysical facies distributions that correlate to facies described in core and thin section samples. Depositionally, sedimentary bedforms (current ripples, graded beds, bioclastic debris layers) documents a depositional setting immediately below or above storm wave base, with deposition from a wide range of traction currents. This suggests deposition in a relatively high energy, shallow water setting, supporting the interpretation of stacked shelf deposits comprising the Second White Specks petroleum system. In addition, analysis of pore size distribution data across the succession provides insights into pore throat morphologies that can be tied to facies distributions. Pore sizes occur as micro-, meso- and macropores (vol %), typically linked to interparticle and grain dissolution, providing insight into storage and flow characteristics for each facies. Collectively, this helps to identify various light oil fairways to be exploited by multistage hydraulically fractured horizontal wells. Panel_14984 Panel_14984 10:10 AM 10:30 AM

There is renewed interest in the shale oil potential of lacustrine rocks because of the recent successful development of a shale oil play in the informal Uteland Butte member of the lacustrine Paleocene and Eocene Green River Formation in the Uinta Basin, Utah using modern horizontal drilling and fracking techniques. The Green River Formation was deposited in large lakes in three intermontane basins in the western interior of the U.S., the Piceance, Uinta, and Greater Green River Basins. These three basins contain the world’s largest in-place oil shale resources with recent estimates of 1.53 trillion, 1.33 trillion, and 1.44 trillion barrels of oil in place in the Piceance, Uinta, and Greater Green River Basins respectively. The Uteland Butte member was deposited in an early freshwater stage of the lake in the Uinta Basin and is a successful shale oil play because it is thermally mature for hydrocarbon generation and contains both organic-rich shale and brittle carbonate rocks. Abnormally high pressures in the “sweet spot” for the Uteland Butte are also important for production. Variations in organic richness of the Uteland Butte were studied using Fischer assay analysis used in the oil shale assessments, and formation pressures were studied using drill-stem tests. Freshwater lacustrine rocks similar to the Uteland Butte member are present in the Piceance and Greater Green River Basins, but these intervals are marginally mature to immature for hydrocarbon generation and contain far less carbonate rocks than the Uteland Butte. Burial histories of the three basins were reconstructed using isopach and structure contour maps. After deposition of the lacustrine interval, rates of subsidence increased in the Uinta Basin and decreased in the Piceance and Greater Green River Basins, thus creating the thermal maturity necessary for a major petroleum system in only the Uinta Basin. There is renewed interest in the shale oil potential of lacustrine rocks because of the recent successful development of a shale oil play in the informal Uteland Butte member of the lacustrine Paleocene and Eocene Green River Formation in the Uinta Basin, Utah using modern horizontal drilling and fracking techniques. The Green River Formation was deposited in large lakes in three intermontane basins in the western interior of the U.S., the Piceance, Uinta, and Greater Green River Basins. These three basins contain the world’s largest in-place oil shale resources with recent estimates of 1.53 trillion, 1.33 trillion, and 1.44 trillion barrels of oil in place in the Piceance, Uinta, and Greater Green River Basins respectively. The Uteland Butte member was deposited in an early freshwater stage of the lake in the Uinta Basin and is a successful shale oil play because it is thermally mature for hydrocarbon generation and contains both organic-rich shale and brittle carbonate rocks. Abnormally high pressures in the “sweet spot” for the Uteland Butte are also important for production. Variations in organic richness of the Uteland Butte were studied using Fischer assay analysis used in the oil shale assessments, and formation pressures were studied using drill-stem tests. Freshwater lacustrine rocks similar to the Uteland Butte member are present in the Piceance and Greater Green River Basins, but these intervals are marginally mature to immature for hydrocarbon generation and contain far less carbonate rocks than the Uteland Butte. Burial histories of the three basins were reconstructed using isopach and structure contour maps. After deposition of the lacustrine interval, rates of subsidence increased in the Uinta Basin and decreased in the Piceance and Greater Green River Basins, thus creating the thermal maturity necessary for a major petroleum system in only the Uinta Basin. Panel_14986 Panel_14986 10:30 AM 10:50 AM

Unconventional drilling and completion techniques, initially established for developing gas shale fairways, are now being used to explore for and exploit the waste zones and transition zones of large fractured carbonate traps. The reservoir in these plays is regionally extensive, but varies widely in quality and structural position relative to free water. Improvement in oil prices and reduction in costs of drilling, completion and lifting technology required to produce and dispose of large volumes of associated water have led to commercial viability of even the poorest zones. The collective group of plays in the Mississippian section in Oklahoma forms a continuum of traps, waste zones, and transition zones in a large inter-connected reservoir system. Water-free oil accumulations in structural traps were discovered and exploited in the middle of the 20th century, using vertical drilling and open-hole completion. Horizontal drilling for these traps in the early part of this century yielded commercial production from thinner reservoirs at moderate oil pricing. Current conditions allow for vertical cased-hole production from down-dip edges and untapped compartments of the discovered conventional traps, as well as horizontal completions with multi-stage hydraulic fracturing in very low permeability reservoir facies of the dense Mississippian Lime. These wells rely on the presence of trapped oil within reservoir-seal couplets that can be gently liberated by horizontal completion, as long as through-going water-bearing vertical fractures can be avoided. With higher oil prices and the use of new 3D seismic, operators are also successfully exploring for complex conventional traps in more highly faulted areas around the Central Oklahoma Fault System and the Nemaha Ridge at the western edge of the Cherokee Platform. Case studies of each of these trap types align in time and space and provide a unified understanding of fluid distribution in the giant Mississippian carbonate system. A similar model describing the distribution of oil and water as a function of the interplay of pore geometry and structure may be at work in other fractured carbonate systems, such as the Permian and Niobrara. Unconventional drilling and completion techniques, initially established for developing gas shale fairways, are now being used to explore for and exploit the waste zones and transition zones of large fractured carbonate traps. The reservoir in these plays is regionally extensive, but varies widely in quality and structural position relative to free water. Improvement in oil prices and reduction in costs of drilling, completion and lifting technology required to produce and dispose of large volumes of associated water have led to commercial viability of even the poorest zones. The collective group of plays in the Mississippian section in Oklahoma forms a continuum of traps, waste zones, and transition zones in a large inter-connected reservoir system. Water-free oil accumulations in structural traps were discovered and exploited in the middle of the 20th century, using vertical drilling and open-hole completion. Horizontal drilling for these traps in the early part of this century yielded commercial production from thinner reservoirs at moderate oil pricing. Current conditions allow for vertical cased-hole production from down-dip edges and untapped compartments of the discovered conventional traps, as well as horizontal completions with multi-stage hydraulic fracturing in very low permeability reservoir facies of the dense Mississippian Lime. These wells rely on the presence of trapped oil within reservoir-seal couplets that can be gently liberated by horizontal completion, as long as through-going water-bearing vertical fractures can be avoided. With higher oil prices and the use of new 3D seismic, operators are also successfully exploring for complex conventional traps in more highly faulted areas around the Central Oklahoma Fault System and the Nemaha Ridge at the western edge of the Cherokee Platform. Case studies of each of these trap types align in time and space and provide a unified understanding of fluid distribution in the giant Mississippian carbonate system. A similar model describing the distribution of oil and water as a function of the interplay of pore geometry and structure may be at work in other fractured carbonate systems, such as the Permian and Niobrara. Panel_14982 Panel_14982 10:50 AM 11:10 AM

The Mid-Continent Mississippian age limestone is a valuable unconventional carbonate reservoir in Oklahoma and Kansas. Although over 14,000 vertical wells have been producing oil and gas from Mississippian age reservoirs for over 50 years, recent horizontal activity has illustrated how crucial it is to understand the petrophysical and depositional characteristics associated with producing intervals. Petrophysical analysis has been integrated with high resolution sequence stratigraphic analyses of core from North-Central Oklahoma to better understand the distribution of reservoir facies in this unconventional carbonate reservoir. Horizontal porosity in the data set, ranges from 0.5-7%, although porosity values may be as high as 20% locally. Correlative permeability ranges from 0.001md to just over 1.0md. SEM analysis shows the pores are mostly oblong to oval, intercrystalline to vuggy, meso- (4mm-62.5 µm) to nanopore (1µm-1nm) size, while pore throat measurements are consistently in the nanopore range. Acoustic response data show the inverse relationship with porosity in unconventional carbonate mudrocks is consistent with previous work using Mesozoic to Cenozoic age conventional carbonates. However, the carbonate mudrock data from the Mississippian show a significant shift in the median value that appears to be consistent with analysis from Neogene carbonate mud samples. Detailed facies analysis from three cores in North-Central Oklahoma suggests deposition occurred on a regionally pervasive, distally steepened carbonate ramp. The facies stack into shoaling upward packages of weakly calcareous mudstones to wackestones at the base, overlain by progressively higher energy skeletal packstone to grainstone facies. A sequence stratigraphic hierarchy of shoaling upward packages is observed in core and wireline logs at the third, fourth, and fifth order scales. Tying the correlation between the wireline log signature and facies stacking patterns into the sequence stratigraphic framework provides a means for increasing the predictability of reservoir quality units in the subsurface. Augmenting this data with the acoustic response, and characterization of the macro- to nanoscale pore architecture, provides an example of how integrated studies can enhance predictability of key reservoir facies and producing intervals within unconventional carbonate reservoirs. The Mid-Continent Mississippian age limestone is a valuable unconventional carbonate reservoir in Oklahoma and Kansas. Although over 14,000 vertical wells have been producing oil and gas from Mississippian age reservoirs for over 50 years, recent horizontal activity has illustrated how crucial it is to understand the petrophysical and depositional characteristics associated with producing intervals. Petrophysical analysis has been integrated with high resolution sequence stratigraphic analyses of core from North-Central Oklahoma to better understand the distribution of reservoir facies in this unconventional carbonate reservoir. Horizontal porosity in the data set, ranges from 0.5-7%, although porosity values may be as high as 20% locally. Correlative permeability ranges from 0.001md to just over 1.0md. SEM analysis shows the pores are mostly oblong to oval, intercrystalline to vuggy, meso- (4mm-62.5 µm) to nanopore (1µm-1nm) size, while pore throat measurements are consistently in the nanopore range. Acoustic response data show the inverse relationship with porosity in unconventional carbonate mudrocks is consistent with previous work using Mesozoic to Cenozoic age conventional carbonates. However, the carbonate mudrock data from the Mississippian show a significant shift in the median value that appears to be consistent with analysis from Neogene carbonate mud samples. Detailed facies analysis from three cores in North-Central Oklahoma suggests deposition occurred on a regionally pervasive, distally steepened carbonate ramp. The facies stack into shoaling upward packages of weakly calcareous mudstones to wackestones at the base, overlain by progressively higher energy skeletal packstone to grainstone facies. A sequence stratigraphic hierarchy of shoaling upward packages is observed in core and wireline logs at the third, fourth, and fifth order scales. Tying the correlation between the wireline log signature and facies stacking patterns into the sequence stratigraphic framework provides a means for increasing the predictability of reservoir quality units in the subsurface. Augmenting this data with the acoustic response, and characterization of the macro- to nanoscale pore architecture, provides an example of how integrated studies can enhance predictability of key reservoir facies and producing intervals within unconventional carbonate reservoirs. Panel_14983 Panel_14983 11:10 AM 11:30 AM

In eastern Canada, the Upper Ordovician Utica Shale has been, since the early days of hydrocarbon exploration in southern Quebec, considered as an excellent hydrocarbon source rock for conventional hydrocarbon systems. The paradigm shift towards its significance for unconventional resource play started in mid-2000 with initial drilling and testing of the Utica Shale with the best IP values of 11 MMcf/d and a stabilized rate after 30 days of 2 MMcf/d. Recent study suggests that Utica Shale is a hybrid resource play with characteristics of mixed reservoirs varying from tight siltstone to organic rich shale. Such a hybrid tight-shale resource play is commonly a closed petroleum system with the crude oil and natural gas originating from organic-rich shale and being stored within the stratigraphic intervals including the tight reservoirs. The matrix porosity may provide the principal storage for expelled petroleum, whereas additional petroleum remains within “organic” pores in the source rock. The matrix and organic pores have very different physical and chemical properties including, water/oil wettability, pore size distribution, and natural gas adsorption capacity. The geological controls of these two porous media types vary significantly and have important implications in resource evaluation. To address the problem of mixed porous media, a dual-porosity model with revised organic porosity estimation is under development and has been applied to the Utica Shale in southern Quebec to evaluate the oil and gas resource potential. This presentation describes the method and recent enhancements and their impact on the resource potential estimation for the Utica Shale in southern Quebec. The new expected in-place resources include 164 TCF of natural gas and 1.8 billion barrels of oil. In eastern Canada, the Upper Ordovician Utica Shale has been, since the early days of hydrocarbon exploration in southern Quebec, considered as an excellent hydrocarbon source rock for conventional hydrocarbon systems. The paradigm shift towards its significance for unconventional resource play started in mid-2000 with initial drilling and testing of the Utica Shale with the best IP values of 11 MMcf/d and a stabilized rate after 30 days of 2 MMcf/d. Recent study suggests that Utica Shale is a hybrid resource play with characteristics of mixed reservoirs varying from tight siltstone to organic rich shale. Such a hybrid tight-shale resource play is commonly a closed petroleum system with the crude oil and natural gas originating from organic-rich shale and being stored within the stratigraphic intervals including the tight reservoirs. The matrix porosity may provide the principal storage for expelled petroleum, whereas additional petroleum remains within “organic” pores in the source rock. The matrix and organic pores have very different physical and chemical properties including, water/oil wettability, pore size distribution, and natural gas adsorption capacity. The geological controls of these two porous media types vary significantly and have important implications in resource evaluation. To address the problem of mixed porous media, a dual-porosity model with revised organic porosity estimation is under development and has been applied to the Utica Shale in southern Quebec to evaluate the oil and gas resource potential. This presentation describes the method and recent enhancements and their impact on the resource potential estimation for the Utica Shale in southern Quebec. The new expected in-place resources include 164 TCF of natural gas and 1.8 billion barrels of oil. Panel_14987 Panel_14987 11:30 AM 11:50 AM

Channels are conduits through which fluids, sediment (suspended and bed-load) and dissolved loads are transported across the Earth surface. Their general geomorphologic expression is comparable similar in terrestrial, submarine and extraterrestrial environments; however, formative sedimentary processes can be fundamentally different. For example, sinuosity and aspect ratio tend to be similar; however, submarine channels tend to be larger than fluvial channels and the stratigraphic records of fluvial and submarine channel deposits can be different. A key research challenge is the link between the geomorphic expression and stratigraphic record of channels. Rivers are more accessible to direct monitoring compared to submarine channels and the link between fluvial geomorphology and stratigraphy is better understood. In the case of submarine channels, we commonly rely on the stratigraphic record to inform insights about formative processes and evolution.

Channels are conduits through which fluids, sediment (suspended and bed-load) and dissolved loads are transported across the Earth surface. Their general geomorphologic expression is comparable similar in terrestrial, submarine and extraterrestrial environments; however, formative sedimentary processes can be fundamentally different. For example, sinuosity and aspect ratio tend to be similar; however, submarine channels tend to be larger than fluvial channels and the stratigraphic records of fluvial and submarine channel deposits can be different. A key research challenge is the link between the geomorphic expression and stratigraphic record of channels. Rivers are more accessible to direct monitoring compared to submarine channels and the link between fluvial geomorphology and stratigraphy is better understood. In the case of submarine channels, we commonly rely on the stratigraphic record to inform insights about formative processes and evolution.

Panel_14420 Panel_14420 8:00 AM 11:50 AM

Panel_15759 Panel_15759 8:00 AM 12:00 AM

Modern rivers are commonly classified as meandering or braided, but this distinction poorly differentiates the range of interval heterogeneities observed in fluvial channel-belt reservoirs. The problem with this division applied to reservoir type is that class definition is based on unrelated variables (sinuosity in one case, and number of active channel threads in the other), and inferences about a range of other variables that are only weakly related (e.g., mean grain size). Large-scale heterogeneity patterns within channel belts are generally not channel-shaped features, but rather reflect bodies formed as channel segments migrate and then are cut off. These bodies (“storeys”) generally scale to formative river discharge (controlling channel width & depth and the downstream length of adjacent bars). The sinuosity of individual channel segments (before cutoff) defines the width/length ratio of these bodies and internal grain size patterns. Deposits within storeys can be divided into different depositional zones with distinct lateral grain-size trends across the channel bed (which can become vertical trends within the deposits by Walters’ law shifts in bed position): inner-bank (bar), concave bank, and abandonment fill. Inward-fining across the inner-bank zone bed becomes more pronounced with distance downstream along a channel bend and channel sinuosity. Upward-fining deposits are preferentially preserved when a channel bend migrates more downstream relative to rates of expansion. Concave bank zone deposits are highly variable depending on whether deposits form due to eddy aggradation or downstream accretion. Channel-fill-zone grain-size trends depend on rates of channel segment abandonment and vertical aggradation vs. lateral-fill deposition. The width of a channel belt formed by a river of given discharge increases with the sinuosity of individual channel segments and the number of storeys laterally stacked during the sum of channel-bend expansion and cutoff events before river avulsion. Connectivity patterns of subsurface fluid flow along a channel belt depends on storey internal character, lateral stacking pattern, net aggradation, and the width spanned by the final fill formed during belt avulsion. Modern rivers are commonly classified as meandering or braided, but this distinction poorly differentiates the range of interval heterogeneities observed in fluvial channel-belt reservoirs. The problem with this division applied to reservoir type is that class definition is based on unrelated variables (sinuosity in one case, and number of active channel threads in the other), and inferences about a range of other variables that are only weakly related (e.g., mean grain size). Large-scale heterogeneity patterns within channel belts are generally not channel-shaped features, but rather reflect bodies formed as channel segments migrate and then are cut off. These bodies (“storeys”) generally scale to formative river discharge (controlling channel width & depth and the downstream length of adjacent bars). The sinuosity of individual channel segments (before cutoff) defines the width/length ratio of these bodies and internal grain size patterns. Deposits within storeys can be divided into different depositional zones with distinct lateral grain-size trends across the channel bed (which can become vertical trends within the deposits by Walters’ law shifts in bed position): inner-bank (bar), concave bank, and abandonment fill. Inward-fining across the inner-bank zone bed becomes more pronounced with distance downstream along a channel bend and channel sinuosity. Upward-fining deposits are preferentially preserved when a channel bend migrates more downstream relative to rates of expansion. Concave bank zone deposits are highly variable depending on whether deposits form due to eddy aggradation or downstream accretion. Channel-fill-zone grain-size trends depend on rates of channel segment abandonment and vertical aggradation vs. lateral-fill deposition. The width of a channel belt formed by a river of given discharge increases with the sinuosity of individual channel segments and the number of storeys laterally stacked during the sum of channel-bend expansion and cutoff events before river avulsion. Connectivity patterns of subsurface fluid flow along a channel belt depends on storey internal character, lateral stacking pattern, net aggradation, and the width spanned by the final fill formed during belt avulsion. Panel_14855 Panel_14855 8:05 AM 8:25 AM

Point bars tend to generate sandy lobate reservoir units that fill channels laterally and serve as primary development targets in both conventional and unconventional fluvial plays. Initial models for point bar growth build upon the presumption of periodic shingling of the convex inner channel bend with sheet-form sand layers that cover much of the wetted bend surface. Episodic and repetitive sheet addition causes the channel to migrate in expansional or translational vectors and produces sandy bodies partitioned with regularly spaced, gently dipping, bar-extensive, and sometimes draped accretion surfaces that record the channel form and resemble large cross sets. This results in reasonably predictable and easily modeled reservoir architectures. While field evidence argues that this fundamental modern process and rock product do occur in some approximation, an accumulation of additional field evidence argues that this process is not alone. At least three other processes also produce point-bar forms, and each of these processes preserves contrasting internal reservoir architecture. These processes are fragmentary bar accretion, counter point bar accretion, and mid-channel bar accretion. Fragmentary bar accretion results from high-frequency deposition of small unit bars over only limited areas of the wetted bar surface, commonly followed by dissection and erosional reshaping of the bar surface and local draping. This results in a bar deposit formed of highly fragmented reservoir units lacking through-going accretion sets and prone to unpredictable heterogeneity. Counter-point-bar accretion occurs by forced decoupling of the cut-bank flow shear and accretion along the cut-bank face. This produces concave accretion surfaces in strata typically much muddier and more heterogeneous than classic convex-accretion bars. Lastly, a lobe sandy body mimicking a true point bar may form in otherwise braided systems by preferential accretion of mid-channel bars to the inside bend of a braided river that meanders. These tend to form sets of amalgamated sandy mid-channel bars into point-bar shapes that have mounded accretion surfaces at various orientations. These surfaces may move reservoir fluid flow in erratic direction. Each of these forms are common, and each includes long internal hiatal surfaces that result in total bar accretion rates that are much slower than rates of short-term bar growth. Point bars tend to generate sandy lobate reservoir units that fill channels laterally and serve as primary development targets in both conventional and unconventional fluvial plays. Initial models for point bar growth build upon the presumption of periodic shingling of the convex inner channel bend with sheet-form sand layers that cover much of the wetted bend surface. Episodic and repetitive sheet addition causes the channel to migrate in expansional or translational vectors and produces sandy bodies partitioned with regularly spaced, gently dipping, bar-extensive, and sometimes draped accretion surfaces that record the channel form and resemble large cross sets. This results in reasonably predictable and easily modeled reservoir architectures. While field evidence argues that this fundamental modern process and rock product do occur in some approximation, an accumulation of additional field evidence argues that this process is not alone. At least three other processes also produce point-bar forms, and each of these processes preserves contrasting internal reservoir architecture. These processes are fragmentary bar accretion, counter point bar accretion, and mid-channel bar accretion. Fragmentary bar accretion results from high-frequency deposition of small unit bars over only limited areas of the wetted bar surface, commonly followed by dissection and erosional reshaping of the bar surface and local draping. This results in a bar deposit formed of highly fragmented reservoir units lacking through-going accretion sets and prone to unpredictable heterogeneity. Counter-point-bar accretion occurs by forced decoupling of the cut-bank flow shear and accretion along the cut-bank face. This produces concave accretion surfaces in strata typically much muddier and more heterogeneous than classic convex-accretion bars. Lastly, a lobe sandy body mimicking a true point bar may form in otherwise braided systems by preferential accretion of mid-channel bars to the inside bend of a braided river that meanders. These tend to form sets of amalgamated sandy mid-channel bars into point-bar shapes that have mounded accretion surfaces at various orientations. These surfaces may move reservoir fluid flow in erratic direction. Each of these forms are common, and each includes long internal hiatal surfaces that result in total bar accretion rates that are much slower than rates of short-term bar growth. Panel_14853 Panel_14853 8:25 AM 8:45 AM

Scaling relationships developed from modern fluvial deposits provide useful guidance for interpretation of the stratigraphic record. At the system level, fluvial channel depth and the related thicknesses of channel-belt sand bodies scale to contributing drainage area, whereas, at the local to subregional level, characteristic width-thickness ratios exist for muddy abandoned channel fills (10-30:1) and laterally amalgamated channel-belt sand bodies (70-300:1). Moreover, net deposition as the river goes through its backwater reach, and feels the effects of sea level, results in significantly less lateral migration before avulsion: although muddy channel-fill dimensions may not change, channel-belt width-to-thickness ratios are significantly less (20-50:1), and sand bodies are encased in muddy flood-basin or delta-plain strata. These and other relationships provide insight into the paleogeographic significance and scale of fluvial deposits in the Early Cretaceous Mannville Group, Alberta foreland. At the system level, thicknesses of Mannville point-bar sand bodies commonly exceed 30 m, which suggests a potential drainage area exceeding that of the modern Mississippi. This view is consistent with detrital-zircon signatures of a source terrain that stretched from the Appalachians in the SE US to the Western Cordillera. These two observations converge to indicate that Mannville fluvial-deltaic deposits record the continental-scale river of that time. At the local to subregional level, the well-imaged Lower Mannville McMurray Formation in Athabasca displays channel-fill dimensions consistent with those from modern rivers, and sand body width-to-thickness ratios typical of amalgamated channel belts within the upper limits of, or above, the backwater reach. Backwater lengths in large river systems with deep, low-gradient channels can exceed 500 km, which would suggest contemporaneous McMurray shorelines would have been very far to the north of the type area. It would be rare to see tidal effects all the way through the backwater reach of any river, and very unlikely to see brackish conditions recorded this far upstream. Yet, sedimentological and ichnofacies characteristics in these deposits have historically been, and still are in many cases, interpreted to record brackish and/or tidal influences. Observations of scaling relationships for channel deposits therefore provide alternative interpretations of McMurray strata that are guiding ongoing investigations. Scaling relationships developed from modern fluvial deposits provide useful guidance for interpretation of the stratigraphic record. At the system level, fluvial channel depth and the related thicknesses of channel-belt sand bodies scale to contributing drainage area, whereas, at the local to subregional level, characteristic width-thickness ratios exist for muddy abandoned channel fills (10-30:1) and laterally amalgamated channel-belt sand bodies (70-300:1). Moreover, net deposition as the river goes through its backwater reach, and feels the effects of sea level, results in significantly less lateral migration before avulsion: although muddy channel-fill dimensions may not change, channel-belt width-to-thickness ratios are significantly less (20-50:1), and sand bodies are encased in muddy flood-basin or delta-plain strata. These and other relationships provide insight into the paleogeographic significance and scale of fluvial deposits in the Early Cretaceous Mannville Group, Alberta foreland. At the system level, thicknesses of Mannville point-bar sand bodies commonly exceed 30 m, which suggests a potential drainage area exceeding that of the modern Mississippi. This view is consistent with detrital-zircon signatures of a source terrain that stretched from the Appalachians in the SE US to the Western Cordillera. These two observations converge to indicate that Mannville fluvial-deltaic deposits record the continental-scale river of that time. At the local to subregional level, the well-imaged Lower Mannville McMurray Formation in Athabasca displays channel-fill dimensions consistent with those from modern rivers, and sand body width-to-thickness ratios typical of amalgamated channel belts within the upper limits of, or above, the backwater reach. Backwater lengths in large river systems with deep, low-gradient channels can exceed 500 km, which would suggest contemporaneous McMurray shorelines would have been very far to the north of the type area. It would be rare to see tidal effects all the way through the backwater reach of any river, and very unlikely to see brackish conditions recorded this far upstream. Yet, sedimentological and ichnofacies characteristics in these deposits have historically been, and still are in many cases, interpreted to record brackish and/or tidal influences. Observations of scaling relationships for channel deposits therefore provide alternative interpretations of McMurray strata that are guiding ongoing investigations. Panel_14849 Panel_14849 8:45 AM 9:05 AM

We introduce a unified geometric model in which the short term fluvio-deltaic processes generating discrete sedimentary bodies and long term basin evolution coexist. Geometric aspects of delta channel networks and their long term internal stratigraphic arrangements of deltaic deposits present enormous intricacy in almost every aspect (delta shape and size, number of channels, shoreline shape, etc.). To simulate the planimetric growth of a deltaic network we employ a flexible algorithm based on a set of simple rules some of which are quantitatively anchored in physical processes while others are purely stochastic and connected to the physical process via observed field correlations among various terms (e.g., Syvitski, 2006). The model generates distributary networks in which planform of individual channels emerge from a correlated random walk algorithm through successive addition of short segments (piecewise). Each segment involves a small direction deflection, partly correlated to the previous deflection. Frequent bifurcations result in dense, anabranching channel patterns while more representative deltaic networks are obtained using a small probability bifurcation value (0.01 to 0.05). The proposed network growth model can yield distributary networks of significant morphological variation in terms of shapes, channel planforms, or channel density. The comparison between model outcomes and field analogs will be through a series of metrics such as planform shape of individual channels, delta shape, shoreline shape, or channel density distribution. Long term, a kinematic basin filling mass conservation model is used to render large scale strata arrangements which under constant sediment supply and sea level conditions consists of monotonous parallel topset and foreset packages. Varying the external forcing factors (i.e., sea level, subsidence) yields complex stratal arrangements reflecting the effects of transgression and incision. We argue that this hybrid approach driven by simple rules is suitable for investigating complex systems. By aggregating only few simple rules, due to the random terms built in, this type of model creates complex landscape patterns via randomness built in (e.g. Murray & Paola, 1994). Using simple rules also enables scenario testing and makes it easier to understand the important controls on the stratigraphic outcome. We introduce a unified geometric model in which the short term fluvio-deltaic processes generating discrete sedimentary bodies and long term basin evolution coexist. Geometric aspects of delta channel networks and their long term internal stratigraphic arrangements of deltaic deposits present enormous intricacy in almost every aspect (delta shape and size, number of channels, shoreline shape, etc.). To simulate the planimetric growth of a deltaic network we employ a flexible algorithm based on a set of simple rules some of which are quantitatively anchored in physical processes while others are purely stochastic and connected to the physical process via observed field correlations among various terms (e.g., Syvitski, 2006). The model generates distributary networks in which planform of individual channels emerge from a correlated random walk algorithm through successive addition of short segments (piecewise). Each segment involves a small direction deflection, partly correlated to the previous deflection. Frequent bifurcations result in dense, anabranching channel patterns while more representative deltaic networks are obtained using a small probability bifurcation value (0.01 to 0.05). The proposed network growth model can yield distributary networks of significant morphological variation in terms of shapes, channel planforms, or channel density. The comparison between model outcomes and field analogs will be through a series of metrics such as planform shape of individual channels, delta shape, shoreline shape, or channel density distribution. Long term, a kinematic basin filling mass conservation model is used to render large scale strata arrangements which under constant sediment supply and sea level conditions consists of monotonous parallel topset and foreset packages. Varying the external forcing factors (i.e., sea level, subsidence) yields complex stratal arrangements reflecting the effects of transgression and incision. We argue that this hybrid approach driven by simple rules is suitable for investigating complex systems. By aggregating only few simple rules, due to the random terms built in, this type of model creates complex landscape patterns via randomness built in (e.g. Murray & Paola, 1994). Using simple rules also enables scenario testing and makes it easier to understand the important controls on the stratigraphic outcome. Panel_14850 Panel_14850 9:05 AM 9:25 AM

Panel_15760 Panel_15760 9:25 AM 12:00 AM

Channels are pervasive features in the modern landscape and stratigraphic record. They occur at various scales in nearly all depositional environments, and represent one of the fundamental reservoir architectures in petroleum systems. This work documents the morphological, kinematic, and architectural changes that channelized systems undergo in the fluvial marine transition (FMT), in terms of physical controls and boundary conditions. In this study, the FMT channels are not considered in isolation. They are compared with other environments (e.g. continental fluvial and deepwater systems) to highlight unique aspects versus commonality in terms of process and product. As the basis of this study, an extensive database of modern systems and shallow analogs has been constructed, sourced from remote sensing, high resolution seismic, and vertical data (core/well). Multiple scales of channelized features are extracted and analyzed including: the geomorphic channel form, oxbow-cutoffs, and channel belts. Geometric statistics measured on these features are used to derive scaling relationships specifically relevant to reservoir characterization. The scaling observations are coupled with known process controls (boundary conditions) to identify and highlight the first order physical controls on channel morphology, kinematics, and resultant architecture. These controls form a process classification that (1) predicts the relative lengthscale of the FMT, ranging from O(< 1 km) to O(1000 km), and (2) polarizes/classifies channelized systems according to process dominance. Process dominance in the FMT is viewed as the significance of episodic fluvial floods in relation to regular tidal flows. The contrasts in morphology that arise from differences in FMT hydrodynamics are mirrored by contrasts in stratigraphy. In particular, the streamwise location of maximum sediment divergence and deposition. As a concrete illustration, we contrast the Mississippi and Amazon systems. Lastly, we examine the interaction of FMT hydrodynamics (the stage-discharge relationship) with relative base level change and avulsion theory, which results in stratigraphic deposits with fundamentally different scaling than their purely fluvial counterparts. Theory coupling hydrodynamic processes, subsidence, and avulsion illustrates the relevance of short-term hydrodynamic processes on the long-term stratigraphic record. Channels are pervasive features in the modern landscape and stratigraphic record. They occur at various scales in nearly all depositional environments, and represent one of the fundamental reservoir architectures in petroleum systems. This work documents the morphological, kinematic, and architectural changes that channelized systems undergo in the fluvial marine transition (FMT), in terms of physical controls and boundary conditions. In this study, the FMT channels are not considered in isolation. They are compared with other environments (e.g. continental fluvial and deepwater systems) to highlight unique aspects versus commonality in terms of process and product. As the basis of this study, an extensive database of modern systems and shallow analogs has been constructed, sourced from remote sensing, high resolution seismic, and vertical data (core/well). Multiple scales of channelized features are extracted and analyzed including: the geomorphic channel form, oxbow-cutoffs, and channel belts. Geometric statistics measured on these features are used to derive scaling relationships specifically relevant to reservoir characterization. The scaling observations are coupled with known process controls (boundary conditions) to identify and highlight the first order physical controls on channel morphology, kinematics, and resultant architecture. These controls form a process classification that (1) predicts the relative lengthscale of the FMT, ranging from O(< 1 km) to O(1000 km), and (2) polarizes/classifies channelized systems according to process dominance. Process dominance in the FMT is viewed as the significance of episodic fluvial floods in relation to regular tidal flows. The contrasts in morphology that arise from differences in FMT hydrodynamics are mirrored by contrasts in stratigraphy. In particular, the streamwise location of maximum sediment divergence and deposition. As a concrete illustration, we contrast the Mississippi and Amazon systems. Lastly, we examine the interaction of FMT hydrodynamics (the stage-discharge relationship) with relative base level change and avulsion theory, which results in stratigraphic deposits with fundamentally different scaling than their purely fluvial counterparts. Theory coupling hydrodynamic processes, subsidence, and avulsion illustrates the relevance of short-term hydrodynamic processes on the long-term stratigraphic record. Panel_14856 Panel_14856 10:10 AM 10:30 AM

Linking stratigraphic and sedimentological attributes of depositional landforms to process dynamics is challenging due to the limited spatial and temporal scales over which measurements may be made relative to the scales that the landforms develop. Here we present process-oriented studies of river and submarine channel levee development, and of floodplain evolution conducted using vastly different scales of observation. Levee development studies were conducted in a laboratory basin on experimental channels a few centimeters deep, while the floodplain studies were conducted using globally available satellite imagery spanning decades. In the laboratory, very high spatial and temporal resolution measurements of jet and density current hydrodynamics and sediment transport were made and linked to patterns of deposition. While these process-based experiments are vastly simplified, relative to natural systems, they provided fundamental insights into the conditions necessary for levee formation at the distal ends of rivers and submarine channels. These insights have served to elucidate how balances in lateral sediment transport and jet dynamics govern deltaic channel formation and provided validation datasets for state of the art morphodynamic models. In submarine systems, the dynamics of density, flow spreading, and entrainment of ambient water critically constrain depositional patterns and highlight fundamental difference between submarine and terrestrial systems despite common channel morphologies. Using multi-temporal satellite imagery we measured of river planform change and floodplain development on rivers systems across the globe. These measurements allow us to use natural systems as experimental realizations from a broad range of settings. This large-scale study of floodplain systems does not provide direct measurements of hydrodynamic and morphodynamics controls, but does provide the opportunity to relate variations in the rate of planform change to other measurable attributes of river systems such as: size, discharge, drainage area, slope, sediment supply and character, climate, and vegetation. These coupled measurements help to isolate the dominant watershed-scale controls on floodplain development and motivate hypotheses on the dominant controls on river mobility. This type of study also has the potential to provide empirical parameterizations for system scale modeling of sedimentology and earth system dynamics. Linking stratigraphic and sedimentological attributes of depositional landforms to process dynamics is challenging due to the limited spatial and temporal scales over which measurements may be made relative to the scales that the landforms develop. Here we present process-oriented studies of river and submarine channel levee development, and of floodplain evolution conducted using vastly different scales of observation. Levee development studies were conducted in a laboratory basin on experimental channels a few centimeters deep, while the floodplain studies were conducted using globally available satellite imagery spanning decades. In the laboratory, very high spatial and temporal resolution measurements of jet and density current hydrodynamics and sediment transport were made and linked to patterns of deposition. While these process-based experiments are vastly simplified, relative to natural systems, they provided fundamental insights into the conditions necessary for levee formation at the distal ends of rivers and submarine channels. These insights have served to elucidate how balances in lateral sediment transport and jet dynamics govern deltaic channel formation and provided validation datasets for state of the art morphodynamic models. In submarine systems, the dynamics of density, flow spreading, and entrainment of ambient water critically constrain depositional patterns and highlight fundamental difference between submarine and terrestrial systems despite common channel morphologies. Using multi-temporal satellite imagery we measured of river planform change and floodplain development on rivers systems across the globe. These measurements allow us to use natural systems as experimental realizations from a broad range of settings. This large-scale study of floodplain systems does not provide direct measurements of hydrodynamic and morphodynamics controls, but does provide the opportunity to relate variations in the rate of planform change to other measurable attributes of river systems such as: size, discharge, drainage area, slope, sediment supply and character, climate, and vegetation. These coupled measurements help to isolate the dominant watershed-scale controls on floodplain development and motivate hypotheses on the dominant controls on river mobility. This type of study also has the potential to provide empirical parameterizations for system scale modeling of sedimentology and earth system dynamics. Panel_14851 Panel_14851 10:50 AM 11:10 AM

A fundamental and long-standing question regarding Mars history is whether the flat and low-lying northern plains ever hosted an ocean. The best opportunity to solve this problem is provided by stratigraphic observations of sedimentary deposits onlapping the crustal dichotomy. In particular, the topographic expression of channelized deposits provides a window into past depositional environments in areas where detailed field observations at the outcrop scale are not possible. Here, we use high-resolution imagery and topography to analyze a branching network of inverted channel and channel lobe deposits in the Aeolis Dorsa region of Mars, just north of the dichotomy boundary. Comparison with terrestrial analogs provides insight to the connection between form and process. At Aeolis Dorsa, Observations of stacked, cross-cutting channel bodies and stratal geometries indicate that these landforms represent exhumed distributary channel deposits. We hypothesize that this distributary system was most likely a delta, rather than an alluvial fan or submarine fan, based on the presence of depositional trunk feeder channel bodies, a lack of evidence for past topographic confinement, channel avulsions at similar elevations, and the presence of a strong break in dip slope between topset and foreset beds. Sediment transport calculations using both measured and derived channel geometries indicate a minimum delta deposition time on the order of 400 years. The location of this delta within a thick and widespread clastic wedge abutting the crustal dichotomy boundary, unconfined by any observable craters, suggests a standing body of water potentially 105 km2 in extent or greater and is spatially consistent with hypotheses for a northern ocean. This work highlights the potential for reconstructing paleo-environment from increasingly high-resolution remote sensing data using terrestrial scaling relationships. A fundamental and long-standing question regarding Mars history is whether the flat and low-lying northern plains ever hosted an ocean. The best opportunity to solve this problem is provided by stratigraphic observations of sedimentary deposits onlapping the crustal dichotomy. In particular, the topographic expression of channelized deposits provides a window into past depositional environments in areas where detailed field observations at the outcrop scale are not possible. Here, we use high-resolution imagery and topography to analyze a branching network of inverted channel and channel lobe deposits in the Aeolis Dorsa region of Mars, just north of the dichotomy boundary. Comparison with terrestrial analogs provides insight to the connection between form and process. At Aeolis Dorsa, Observations of stacked, cross-cutting channel bodies and stratal geometries indicate that these landforms represent exhumed distributary channel deposits. We hypothesize that this distributary system was most likely a delta, rather than an alluvial fan or submarine fan, based on the presence of depositional trunk feeder channel bodies, a lack of evidence for past topographic confinement, channel avulsions at similar elevations, and the presence of a strong break in dip slope between topset and foreset beds. Sediment transport calculations using both measured and derived channel geometries indicate a minimum delta deposition time on the order of 400 years. The location of this delta within a thick and widespread clastic wedge abutting the crustal dichotomy boundary, unconfined by any observable craters, suggests a standing body of water potentially 105 km² in extent or greater and is spatially consistent with hypotheses for a northern ocean. This work highlights the potential for reconstructing paleo-environment from increasingly high-resolution remote sensing data using terrestrial scaling relationships. Panel_14852 Panel_14852 11:10 AM 11:30 AM

Channels act as arteries for the transport of sediment across landscapes and seascapes and help distribute this sediment in basins where thick stratigraphic packages accumulate. Quantitative observations of the planform morphologies of channels in terrestrial and submarine settings indicate strong similarity, suggesting similar transport processes and morphodynamics in the two settings. Observations of these systems in cross-section, however, indicate great differences in their morphologies which likely arise from differences in transport processes and morphodynamics. While significant attention has recently been paid to short time scale differences/similarities of open channel flows and turbidity currents (e.g. direction of helical flow in channel bends) here we focus on a comparison of these flow types and their stratigraphic records over basin filling time scales. In the terrestrial, the ratio for the densities of the channelized flow and the ambient fluid it is moving through is roughly 800. This condition leads to one in which rivers are prone to avulse when they superelevate to a value roughly equal to a channel depth. Coupled with the generation of a backwater regime where terrestrial channels approach the shoreline, the strong difference in flow to ambient fluid densities results in abandoned channels which are topographic lows on landscapes. This condition promotes reoccupation of old channel paths following avulsions and the generation of persistent depositional trends, such as channel clustering. In contrast, the ratio of current to ambient fluid density for turbidity currents in the submarine is only slightly greater than unity. In settings where normal flow dominates, this allows submarine channels to superelevate several multiples of their channel depth. These conditions result in abandoned channels that remain high for a time, leading to avoidance of previous channels and an overall tendency to distribute channel bodies. Further complicating matters though, is the widespread occurrence of non-normal flow in turbidity currents, which in terminal fan settings might lead to stratigraphic architecture similar to terrestrial settings. We explore these processes and products using observations from modern systems and ancient stratigraphic architecture in addition to results from reduced complexity models. Channels act as arteries for the transport of sediment across landscapes and seascapes and help distribute this sediment in basins where thick stratigraphic packages accumulate. Quantitative observations of the planform morphologies of channels in terrestrial and submarine settings indicate strong similarity, suggesting similar transport processes and morphodynamics in the two settings. Observations of these systems in cross-section, however, indicate great differences in their morphologies which likely arise from differences in transport processes and morphodynamics. While significant attention has recently been paid to short time scale differences/similarities of open channel flows and turbidity currents (e.g. direction of helical flow in channel bends) here we focus on a comparison of these flow types and their stratigraphic records over basin filling time scales. In the terrestrial, the ratio for the densities of the channelized flow and the ambient fluid it is moving through is roughly 800. This condition leads to one in which rivers are prone to avulse when they superelevate to a value roughly equal to a channel depth. Coupled with the generation of a backwater regime where terrestrial channels approach the shoreline, the strong difference in flow to ambient fluid densities results in abandoned channels which are topographic lows on landscapes. This condition promotes reoccupation of old channel paths following avulsions and the generation of persistent depositional trends, such as channel clustering. In contrast, the ratio of current to ambient fluid density for turbidity currents in the submarine is only slightly greater than unity. In settings where normal flow dominates, this allows submarine channels to superelevate several multiples of their channel depth. These conditions result in abandoned channels that remain high for a time, leading to avoidance of previous channels and an overall tendency to distribute channel bodies. Further complicating matters though, is the widespread occurrence of non-normal flow in turbidity currents, which in terminal fan settings might lead to stratigraphic architecture similar to terrestrial settings. We explore these processes and products using observations from modern systems and ancient stratigraphic architecture in addition to results from reduced complexity models. Panel_14854 Panel_14854 11:30 AM 11:50 AM

Panel_14460 Panel_14460 8:00 AM 11:50 AM

Panel_15798 Panel_15798 8:00 AM 12:00 AM

It is well known that many turbidity currents originate on the upper continental slope, accelerate downslope and then deposit much of their sediment load on the deep basin floor. What's less clear is how these currents are able to achieve run-out distances of hundreds to thousands of kilometers along the basin floor under virtually zero grade conditions. Although numerous researchers have suggested that this is related to the internal momentum of the flow, obtaining simultaneous high-resolution velocity and density datasets of sediment gravity currents is notoriously difficult. Consequently, many experimental studies employ saline density currents as surrogates for particle gravity flows, even though it is unclear how suitable they are as proxies for explaining run-out distances since they omit the effects of varying particle settling velocities and fluid-particle and particle-particle interactions, all which must have played some, if not major role in governing the internal characteristics of the turbidity currents. Here we report on a series of experiments that paired a three-dimensional ultrasonic Doppler velocity profiler (UDVP-3D) and a medical grade computed tomography (CT) scanner to simultaneously examine the velocity and density structure of sediment gravity currents across a range of particle sizes (d50: 70, 150, 230, 330 µm) and sediment concentrations (~5-18% by mass; 2-8 sediment volume %). Results show that compared to coarser-grained flows, finer-grained flows are less density stratified, have a more bulbous velocity profile and the high velocity core is positioned higher above the bed. Reduced density stratification, in addition to reduced grain settling velocity and increased particle-particle interactions, controls the shape of the velocity profile, which in fine-grained flow leads to a more symmetric (“plug-like”) profile between the bed and the top of the boundary layer. It is this more vertically uniform density structure in fine-grained flows, rather than the velocity profile, that controls the local momentum gradient, and as a consequence reduces mixing between the current and the ambient fluid. Reduced mixing allows these flows to retain more of their initial momentum, and accordingly, promotes longer run-out distance across a virtually horizontal deep basin floor. It is well known that many turbidity currents originate on the upper continental slope, accelerate downslope and then deposit much of their sediment load on the deep basin floor. What's less clear is how these currents are able to achieve run-out distances of hundreds to thousands of kilometers along the basin floor under virtually zero grade conditions. Although numerous researchers have suggested that this is related to the internal momentum of the flow, obtaining simultaneous high-resolution velocity and density datasets of sediment gravity currents is notoriously difficult. Consequently, many experimental studies employ saline density currents as surrogates for particle gravity flows, even though it is unclear how suitable they are as proxies for explaining run-out distances since they omit the effects of varying particle settling velocities and fluid-particle and particle-particle interactions, all which must have played some, if not major role in governing the internal characteristics of the turbidity currents. Here we report on a series of experiments that paired a three-dimensional ultrasonic Doppler velocity profiler (UDVP-3D) and a medical grade computed tomography (CT) scanner to simultaneously examine the velocity and density structure of sediment gravity currents across a range of particle sizes (d50: 70, 150, 230, 330 µm) and sediment concentrations (~5-18% by mass; 2-8 sediment volume %). Results show that compared to coarser-grained flows, finer-grained flows are less density stratified, have a more bulbous velocity profile and the high velocity core is positioned higher above the bed. Reduced density stratification, in addition to reduced grain settling velocity and increased particle-particle interactions, controls the shape of the velocity profile, which in fine-grained flow leads to a more symmetric (“plug-like”) profile between the bed and the top of the boundary layer. It is this more vertically uniform density structure in fine-grained flows, rather than the velocity profile, that controls the local momentum gradient, and as a consequence reduces mixing between the current and the ambient fluid. Reduced mixing allows these flows to retain more of their initial momentum, and accordingly, promotes longer run-out distance across a virtually horizontal deep basin floor. Panel_15243 Panel_15243 8:05 AM 8:25 AM

Transitional flows deposits have been described in a wide range of deepwater basins such as the Agadir Basin (offshore Morocco), Britannia Formation in the North Sea and the ultra-deepwater sub-salt Wilcox Group (USA). These types of deposits do not follow the ‘classic’ deepwater facies models (i.e., Bouma Sequence). One of the most enigmatic aspects of transitional flow deposits lies in an alternation between clay-rich and clean sand bands. Distinguishing between laminae and true banding in argillaceous deepwater deposits is often unclear due to uncertainty in the processes controlling the development of banding. Surging within depositing sediment gravity flows may provide a process-based explanation for why banded intervals are common in facies descriptions of transitional flow deposits. To test this hypothesis, we induced intermittent surges on clay-rich, sand-laden transitional flows in a two-dimensional experimental flume. Surging produces unsteady deposition of alternating clay-rich and clean sand bands in an overall fining upward event bed. Millimeter-scale bands are connected to fluctuating bed aggradation rates which wax and wane in response to surging. High-resolution videos taken during the experiments show that rapid bed aggradation results in clay-rich bands while lower aggradation rates deposit relatively clean sands. The character of banding differs across the tested flow compositions, from high-concentration turbidity currents to strong transitional flows. Variability in the spatial distribution of clay within banded deepwater deposits has implications for predicting both permeability structure and overall reservoir quality. Transitional flows deposits have been described in a wide range of deepwater basins such as the Agadir Basin (offshore Morocco), Britannia Formation in the North Sea and the ultra-deepwater sub-salt Wilcox Group (USA). These types of deposits do not follow the ‘classic’ deepwater facies models (i.e., Bouma Sequence). One of the most enigmatic aspects of transitional flow deposits lies in an alternation between clay-rich and clean sand bands. Distinguishing between laminae and true banding in argillaceous deepwater deposits is often unclear due to uncertainty in the processes controlling the development of banding. Surging within depositing sediment gravity flows may provide a process-based explanation for why banded intervals are common in facies descriptions of transitional flow deposits. To test this hypothesis, we induced intermittent surges on clay-rich, sand-laden transitional flows in a two-dimensional experimental flume. Surging produces unsteady deposition of alternating clay-rich and clean sand bands in an overall fining upward event bed. Millimeter-scale bands are connected to fluctuating bed aggradation rates which wax and wane in response to surging. High-resolution videos taken during the experiments show that rapid bed aggradation results in clay-rich bands while lower aggradation rates deposit relatively clean sands. The character of banding differs across the tested flow compositions, from high-concentration turbidity currents to strong transitional flows. Variability in the spatial distribution of clay within banded deepwater deposits has implications for predicting both permeability structure and overall reservoir quality. Panel_15244 Panel_15244 8:25 AM 8:45 AM

Low permeability, muddy sandstone reservoirs in ultra-deepwater fan systems present considerable challenges for reservoir predictions at multiple scales. Understanding the spatial facies distributions in channelized lobe systems can be complex due to the variable sediment-flow types, from turbulent to transitional to laminar, that create them. A set of physical experiments were used to investigate the evolution of lobe properties associated with stacked three dimensional deposits. Multiple high concentration, clay-rich sand-laden transitional flows were released into an unconfined slope-basin setting. Individual flow events were distinguished by varying the color of the coarsest sand fraction. Twenty seven freeze core samples of the final deposit were used to explore the spatial distribution, relative thickness and degree of mixing of colored sand and mud. Grain size and sorting analysis of the unmixed and mixed layers of sand and mud at multiple locations in the deposit are used to identify vertical and horizontal trends. These trends are compared to the local topographic and deposit thickness variations. These experiments provide insight into the spatial facies distributions of muddy sandstones in lobe systems, with relatively clean sands occurring near the deposit axis and muddier sands at the margins. Low permeability, muddy sandstone reservoirs in ultra-deepwater fan systems present considerable challenges for reservoir predictions at multiple scales. Understanding the spatial facies distributions in channelized lobe systems can be complex due to the variable sediment-flow types, from turbulent to transitional to laminar, that create them. A set of physical experiments were used to investigate the evolution of lobe properties associated with stacked three dimensional deposits. Multiple high concentration, clay-rich sand-laden transitional flows were released into an unconfined slope-basin setting. Individual flow events were distinguished by varying the color of the coarsest sand fraction. Twenty seven freeze core samples of the final deposit were used to explore the spatial distribution, relative thickness and degree of mixing of colored sand and mud. Grain size and sorting analysis of the unmixed and mixed layers of sand and mud at multiple locations in the deposit are used to identify vertical and horizontal trends. These trends are compared to the local topographic and deposit thickness variations. These experiments provide insight into the spatial facies distributions of muddy sandstones in lobe systems, with relatively clean sands occurring near the deposit axis and muddier sands at the margins. Panel_15249 Panel_15249 8:45 AM 9:05 AM

Interpretations of submarine channel deposits are often over-shadowed by a few basic questions: Were turbidity currents contained within the channel? What were their concentrations? What were their velocities? How thick were they? These parameters are necessary inputs in many computational models. We will present estimates of the hydraulic characteristics of paleo-flows responsible for sediment sorting within the Brushy Canyon Formation channel deposits, on the upper-slope and basin floor of the Paleozoic Delaware Basin. The depositional facies on the upper slope fall into two broad classes: A) open-channel facies associated with bypass of sediment to deeper water; and B) channel-filling facies associated with bed aggradation and significant loss of channel relief. Deposits accumulating during bypass are interpreted to be eddy bars located in bank-attached zones of flow separation. These deposits are characterized by packages of steeply inclined beds composed of planar-stratified, trough cross-stratified or sub- to super-critically climbing rippled deposits (D50=110µm). The channel-filling deposits form thick-bedded, sometimes gravel-rich, sandstone bodies which are structureless or which display stratification associated with migrating dunes and intra-channel barforms (D50=156µm). On the proximal basin floor, the channel-filling sandstones (D50=110µm) are dominated by stratification associated with trains of dunes climbing at sub- to super-critical angles, indicating high rates of deposition from suspension. We use modified sediment transport relationships, originally developed for fluvial environments, to characterize the bulk properties of paleo-flows that constructed turbidite strata in the Brushy Canyon channels. Bed geometries, sedimentary structures and grain-size data, used with these relationships, show that the studied channel strata were constructed from turbidity currents that were dilute (concentrations less than 5%), had depth-averaged velocities between 0.96-1.56m/s and were at least 15m thick. Interpretations of submarine channel deposits are often over-shadowed by a few basic questions: Were turbidity currents contained within the channel? What were their concentrations? What were their velocities? How thick were they? These parameters are necessary inputs in many computational models. We will present estimates of the hydraulic characteristics of paleo-flows responsible for sediment sorting within the Brushy Canyon Formation channel deposits, on the upper-slope and basin floor of the Paleozoic Delaware Basin. The depositional facies on the upper slope fall into two broad classes: A) open-channel facies associated with bypass of sediment to deeper water; and B) channel-filling facies associated with bed aggradation and significant loss of channel relief. Deposits accumulating during bypass are interpreted to be eddy bars located in bank-attached zones of flow separation. These deposits are characterized by packages of steeply inclined beds composed of planar-stratified, trough cross-stratified or sub- to super-critically climbing rippled deposits (D50=110µm). The channel-filling deposits form thick-bedded, sometimes gravel-rich, sandstone bodies which are structureless or which display stratification associated with migrating dunes and intra-channel barforms (D50=156µm). On the proximal basin floor, the channel-filling sandstones (D50=110µm) are dominated by stratification associated with trains of dunes climbing at sub- to super-critical angles, indicating high rates of deposition from suspension. We use modified sediment transport relationships, originally developed for fluvial environments, to characterize the bulk properties of paleo-flows that constructed turbidite strata in the Brushy Canyon channels. Bed geometries, sedimentary structures and grain-size data, used with these relationships, show that the studied channel strata were constructed from turbidity currents that were dilute (concentrations less than 5%), had depth-averaged velocities between 0.96-1.56m/s and were at least 15m thick. Panel_15241 Panel_15241 9:05 AM 9:25 AM

Panel_15813 Panel_15813 9:25 AM 12:00 AM

Observations and interpretations of sedimentary facies in deep-marine lobe deposits have been strongly influenced by models developed from relatively small, coarse-grained foreland basins. Whilst these models are valid for similar systems, today’s ultra deep-water subsurface exploration targets are typically associated with sedimentary systems that are up to orders of magnitude larger, with a much narrower grain-size range. In this contribution, the spatial and stratigraphic distribution of the various facies associated with a fine-grained, deep-marine lobe complex (Fan 3, Skoorsteenberg Fm., Tanqua Karoo) are presented and characterized to improve understanding sediment transport processes in such environments. The stratigraphy of Fan 3 is exceptionally well-exposed and well-constrained, making it an ideal place to observe this variability. The dataset includes helicopter-based photomosaics, measured sections and thin sections from oriented samples. QEMSCAN® (Quantitative Evaluation of Minerals by SCANning electron microscopy) analysis, including mineralogical and textural analysis of different bed types, was undertaken to support outcrop observations. Grain-size distributions, including quantification of clay content, can be established from these data and, in conjunction with the outcrop data demonstrate a progressive enrichment of clay and fine grained particles towards the distal and marginal parts Fan 3 lobes. It is demonstrated that predictable spatial and stratigraphic facies distributions can be recognised. Her, this distribution is attributed to an increase in near bed flow concentration due to flow deceleration and collapse in response to flow expansion and entrainment of clay and silt from the substrate; this is recorded in the deposits, from axis to off-axis positions, by increased clay content, decreased erosional capability of flows and progressively stronger internal deposit heterogeneity. The model differs from previous models as the flow transformation is thought to be highly localized, occurring due to autocyclic flow evolution in medial to distal lobe localities; the model and quantification of flow transformation distance has important implications for estimating the spatial and stratigraphic distributions of heterogeneities/reservoir quality for such beds in deep-marine lobe deposits, which in many areas form important hydrocarbon reservoirs, and for interpreting the significance of these deposits in core and outcrop datasets. Observations and interpretations of sedimentary facies in deep-marine lobe deposits have been strongly influenced by models developed from relatively small, coarse-grained foreland basins. Whilst these models are valid for similar systems, today’s ultra deep-water subsurface exploration targets are typically associated with sedimentary systems that are up to orders of magnitude larger, with a much narrower grain-size range. In this contribution, the spatial and stratigraphic distribution of the various facies associated with a fine-grained, deep-marine lobe complex (Fan 3, Skoorsteenberg Fm., Tanqua Karoo) are presented and characterized to improve understanding sediment transport processes in such environments. The stratigraphy of Fan 3 is exceptionally well-exposed and well-constrained, making it an ideal place to observe this variability. The dataset includes helicopter-based photomosaics, measured sections and thin sections from oriented samples. QEMSCAN® (Quantitative Evaluation of Minerals by SCANning electron microscopy) analysis, including mineralogical and textural analysis of different bed types, was undertaken to support outcrop observations. Grain-size distributions, including quantification of clay content, can be established from these data and, in conjunction with the outcrop data demonstrate a progressive enrichment of clay and fine grained particles towards the distal and marginal parts Fan 3 lobes. It is demonstrated that predictable spatial and stratigraphic facies distributions can be recognised. Her, this distribution is attributed to an increase in near bed flow concentration due to flow deceleration and collapse in response to flow expansion and entrainment of clay and silt from the substrate; this is recorded in the deposits, from axis to off-axis positions, by increased clay content, decreased erosional capability of flows and progressively stronger internal deposit heterogeneity. The model differs from previous models as the flow transformation is thought to be highly localized, occurring due to autocyclic flow evolution in medial to distal lobe localities; the model and quantification of flow transformation distance has important implications for estimating the spatial and stratigraphic distributions of heterogeneities/reservoir quality for such beds in deep-marine lobe deposits, which in many areas form important hydrocarbon reservoirs, and for interpreting the significance of these deposits in core and outcrop datasets. Panel_15245 Panel_15245 10:10 AM 10:30 AM

Sediments deposited in overbank areas adjacent to submarine channels record the history of turbidity current activity within the channels. Overbank areas include levees, which decrease in height away from the channels that they confine, often with predictable thickness decay. The modern turbidite system in the Gioia Basin (Sicilian margin of the Tyrrhenian Sea, Italy) consists of three different levee-bound slope channels with separations up to 10 km. Two of these channels are sub-parallel while the third is roughly perpendicular to the others. We have used CHIRP sub-bottom profiles and multi-beam bathymetric data to interpret the distribution of near-surface acoustic facies across this part of the Sicilian margin. These facies have been mapped and calibrated using shallow cores (gravity, piston and box cores). The cores were correlated using sedimentary logs and magnetic susceptibility measurements. The integrated interpretation of the available data reveals complex geometries and facies relationships that would be difficult to identify in outcrop or the subsurface. The magnetic susceptibility measurements of the cores show that the upper five metres of sediment on the levees of two of the three channels have similar signatures. This indicates that these two channels have a similar record of activity, implying simultaneous turbidity currents in both channels. The acoustic facies distribution and bathymetry show interactions between overbank flow from the three separate channels. This interaction creates complex topography, including sediment waves and scours that modify the levee/overbank geometries, and divert sediment to depositional areas further from the channel. Further complexity is introduced where the levee of the third channel, which runs perpendicular to the other two, is filling one of the other channels. Sediment-draped abandoned channels and levees also occur in the overbank areas, adding further complexity. Modern seafloor data show the interactions between multiple synchronously active channels and their levees, and reveal how the architecture of levees may depart from established thickness decay models. Channels that are in close proximity but which are active at different times can add to the complexity of the stratigraphic record. Awareness of these potential complications is vital when interpreting subsurface data. Sediments deposited in overbank areas adjacent to submarine channels record the history of turbidity current activity within the channels. Overbank areas include levees, which decrease in height away from the channels that they confine, often with predictable thickness decay. The modern turbidite system in the Gioia Basin (Sicilian margin of the Tyrrhenian Sea, Italy) consists of three different levee-bound slope channels with separations up to 10 km. Two of these channels are sub-parallel while the third is roughly perpendicular to the others. We have used CHIRP sub-bottom profiles and multi-beam bathymetric data to interpret the distribution of near-surface acoustic facies across this part of the Sicilian margin. These facies have been mapped and calibrated using shallow cores (gravity, piston and box cores). The cores were correlated using sedimentary logs and magnetic susceptibility measurements. The integrated interpretation of the available data reveals complex geometries and facies relationships that would be difficult to identify in outcrop or the subsurface. The magnetic susceptibility measurements of the cores show that the upper five metres of sediment on the levees of two of the three channels have similar signatures. This indicates that these two channels have a similar record of activity, implying simultaneous turbidity currents in both channels. The acoustic facies distribution and bathymetry show interactions between overbank flow from the three separate channels. This interaction creates complex topography, including sediment waves and scours that modify the levee/overbank geometries, and divert sediment to depositional areas further from the channel. Further complexity is introduced where the levee of the third channel, which runs perpendicular to the other two, is filling one of the other channels. Sediment-draped abandoned channels and levees also occur in the overbank areas, adding further complexity. Modern seafloor data show the interactions between multiple synchronously active channels and their levees, and reveal how the architecture of levees may depart from established thickness decay models. Channels that are in close proximity but which are active at different times can add to the complexity of the stratigraphic record. Awareness of these potential complications is vital when interpreting subsurface data. Panel_15122 Panel_15122 10:30 AM 10:50 AM

Hybrid event beds (HEBs) are a type sediment gravity flow deposits that generally comprises a basal clean sandstone (H1) overlain by a muddier and less-permeable sandy facies (H3) emplaced during the same transport event. They are commonly found in association with conventional turbidites in the distal and marginal reaches of many ancient deep-water systems; they are important in both exploration and appraisal because their presence and character is not readily predictable and they compromise reservoir performance. The Cretaceous-Palaeocene Gottero turbidite system of NW of Italy developed on the Ligurian convergent margin, transforming from a passive margin basin floor fan to a trench-slope system. Detailed fieldwork, including collection of >4000 m of graphic logs, has shown that HEBs are abundant in the outer fan portion of the system, where they comprise more than 50% of the event beds. In more proximal sectors HEBs occur interbedded with mid-fan sandstone lobes, and may comprise up to 6% of event beds. They are apparently absent in the inner fan, channelised area. The origin of HEBs in the outer and mid-fan sectors is different and is thought to be controlled by the flow magnitude and the loci of mud entrainment by substrate erosion. The outer fan sector is dominated by thick and tabular mudclast-rich HEBs, generated by highly energetic flows capable of eroding the sea-floor locally, sometimes detaching large pieces of substrate by basal injection, and carrying them over relatively short distances as muddy rafts. A number of genetically-related bed types can be recognised, in which the disaggregation of the muddy particles along longitudinal facies tracts progressively leads to the development of a cohesive linked-debrite character to the H3 division. These bed types exhibit rapid internal lateral facies changes developed mainly along depositional strike. In the mid-fan sector thinner HEBs with highly mixed, clast-poor and disaggregated H3 divisions accumulate in muddy interlobe intervals between amalgamated sandstone lobes, and are thought to have been produced by less energetic flows that underwent early turbulence damping following incorporation of cohesive mud from the substrate. The various HEBs bed types and their stratigraphic and lateral distribution are integrated into a new predictive depositional model in order to characterise the high degree of complexity of the hybrid-prone facies associations inside turbidite fans of this type and setting. Hybrid event beds (HEBs) are a type sediment gravity flow deposits that generally comprises a basal clean sandstone (H1) overlain by a muddier and less-permeable sandy facies (H3) emplaced during the same transport event. They are commonly found in association with conventional turbidites in the distal and marginal reaches of many ancient deep-water systems; they are important in both exploration and appraisal because their presence and character is not readily predictable and they compromise reservoir performance. The Cretaceous-Palaeocene Gottero turbidite system of NW of Italy developed on the Ligurian convergent margin, transforming from a passive margin basin floor fan to a trench-slope system. Detailed fieldwork, including collection of >4000 m of graphic logs, has shown that HEBs are abundant in the outer fan portion of the system, where they comprise more than 50% of the event beds. In more proximal sectors HEBs occur interbedded with mid-fan sandstone lobes, and may comprise up to 6% of event beds. They are apparently absent in the inner fan, channelised area. The origin of HEBs in the outer and mid-fan sectors is different and is thought to be controlled by the flow magnitude and the loci of mud entrainment by substrate erosion. The outer fan sector is dominated by thick and tabular mudclast-rich HEBs, generated by highly energetic flows capable of eroding the sea-floor locally, sometimes detaching large pieces of substrate by basal injection, and carrying them over relatively short distances as muddy rafts. A number of genetically-related bed types can be recognised, in which the disaggregation of the muddy particles along longitudinal facies tracts progressively leads to the development of a cohesive linked-debrite character to the H3 division. These bed types exhibit rapid internal lateral facies changes developed mainly along depositional strike. In the mid-fan sector thinner HEBs with highly mixed, clast-poor and disaggregated H3 divisions accumulate in muddy interlobe intervals between amalgamated sandstone lobes, and are thought to have been produced by less energetic flows that underwent early turbulence damping following incorporation of cohesive mud from the substrate. The various HEBs bed types and their stratigraphic and lateral distribution are integrated into a new predictive depositional model in order to characterise the high degree of complexity of the hybrid-prone facies associations inside turbidite fans of this type and setting. Panel_15246 Panel_15246 10:50 AM 11:10 AM

It is increasingly recognized that sediment gravity flow deposits often defy classical turbidite-debrite models and are wide ranging in character (e.g., slurry beds, hybrid event beds and transitional flow deposits). Such deposits, here collectively referred to as hybrid event beds (HEBs) are of importance as they cause heterogeneities in reservoir quality distribution from intra-bed to system scales. HEBs are inferred to record deposition beneath flow characterised by discrete internal rheological zones, ranging from turbulent to laminar, whose relative proportions within the flow evolved both spatially and temporally. The high clay concentration in these deposits could reflect preferential deposition of the coarser sand fraction, and hence a relative clay enrichment, and/or an actual enrichment through entrainment of muddy substrate into the flow. In topographically-influenced systems it has been suggests HEBs may indicate proximity to confining slopes due to their localised occurrence and systematic depositional variation towards such features. New research from a range of systems developed within basins of differing physiography (e.g., unconfined, confined and contained [ponded]) has begun to highlight contrasts in the depositional character and distribution of HEBs between these settings. Specifically; 1) the relative degree of flow transformation undergone by the parent hybrid flow, as expressed by the degree of textural and compositional segregation within HEBs, and how argillaceous (clay-rich) their deposits are; 2) the degree of lateral variation in HEB depositional character over short (10s – 100s metres) and longer (100s – 1000s metres) length scales, and whether such variation is systematic or not; 3) whether HEBs are localized to confining sea-floor topography and exhibit depositional trends towards such features; 4) the range of potential stratigraphic stacking patterns developed in these systems. Characteristics of HEBs in different system types are thought to reflect variations in the initial flow character, substrate entrainment, flow confinement, flow containment and flow run-out distance achieved and their influences upon the processes that promote flow evolution and transformation. This work highlights the range of boundary conditions to be considered when attempting to predict the spatial occurrence and depositional character of these non-classical deposits, and thus reservoir quality distribution, within deep-water systems. It is increasingly recognized that sediment gravity flow deposits often defy classical turbidite-debrite models and are wide ranging in character (e.g., slurry beds, hybrid event beds and transitional flow deposits). Such deposits, here collectively referred to as hybrid event beds (HEBs) are of importance as they cause heterogeneities in reservoir quality distribution from intra-bed to system scales. HEBs are inferred to record deposition beneath flow characterised by discrete internal rheological zones, ranging from turbulent to laminar, whose relative proportions within the flow evolved both spatially and temporally. The high clay concentration in these deposits could reflect preferential deposition of the coarser sand fraction, and hence a relative clay enrichment, and/or an actual enrichment through entrainment of muddy substrate into the flow. In topographically-influenced systems it has been suggests HEBs may indicate proximity to confining slopes due to their localised occurrence and systematic depositional variation towards such features. New research from a range of systems developed within basins of differing physiography (e.g., unconfined, confined and contained [ponded]) has begun to highlight contrasts in the depositional character and distribution of HEBs between these settings. Specifically; 1) the relative degree of flow transformation undergone by the parent hybrid flow, as expressed by the degree of textural and compositional segregation within HEBs, and how argillaceous (clay-rich) their deposits are; 2) the degree of lateral variation in HEB depositional character over short (10s – 100s metres) and longer (100s – 1000s metres) length scales, and whether such variation is systematic or not; 3) whether HEBs are localized to confining sea-floor topography and exhibit depositional trends towards such features; 4) the range of potential stratigraphic stacking patterns developed in these systems. Characteristics of HEBs in different system types are thought to reflect variations in the initial flow character, substrate entrainment, flow confinement, flow containment and flow run-out distance achieved and their influences upon the processes that promote flow evolution and transformation. This work highlights the range of boundary conditions to be considered when attempting to predict the spatial occurrence and depositional character of these non-classical deposits, and thus reservoir quality distribution, within deep-water systems. Panel_15248 Panel_15248 11:10 AM 11:30 AM

Structural deformation in tectonically active margins can be accompanied by mass wasting and the emplacement of mass transport complexes (MTCs). MTCs may both erode and deposit along their flow pathways, generating topography that affects later flows and their deposit characteristics. Here, we investigate the role that bathymetrically complex substrates may play in modifying debris flow erosion and sedimentation patterns. The study is based on detailed near-surface mapping of a 1900 km2 3D seismic volume from the southern Magdalena Fan, offshore Colombia. The study area is characterized by two NE-trending anticlines that form the northern tip of the Southern Sinú Fold Belt. In front of the structures, a 200 m thick MTC overlies an erosional surface. The horizons interpreted as the top and base of the deposit can be continuously mapped across the study area; however, grooves on the basal shear surface reveal three transport directions linked to separate headwalls along the frontal fringe of the fold belt, and thus indicate the coalescence of several flow events into a composite MTC. Here we focus on the central MTC, which can be traced updip across the northern plunge of the southern anticline to the steep frontal limb of another structure at the edge of the data set. The emplacing flow initially trended NW, but was deflected to the SW upon encountering the back limb of the northern anticline. It changed trend again where it crossed the southern anticlinal structure through a narrow notch. Updip of this structure, the erosional relief is 500 m, and the deposit is 6 km wide, 100 m thick, and is composed of debrites and isolated blocks. As it traversed the structure, basal relief reduced to 250 m and the deposit, which is mainly composed of blocks, is only 40 m thick and 3 km wide. Downdip of the structures, the erosional surface widens to 16 km and is almost entirely filled by a 200 m thick unit composed of chaotic and folded reflectors and blocks. Here, the crest of an underlying levee directed the flow to the SW and is overlain by blocks aligned parallel to the direction of flow. The response of MTCs to underlying bathymetry can be reflected in their flow pathways, erosional relief and in the characteristics of the deposits. The presence of blocks, internal deformation, changes in thickness and matrix content can all be influenced by the interaction between MTCs and irregular substrates. Structural deformation in tectonically active margins can be accompanied by mass wasting and the emplacement of mass transport complexes (MTCs). MTCs may both erode and deposit along their flow pathways, generating topography that affects later flows and their deposit characteristics. Here, we investigate the role that bathymetrically complex substrates may play in modifying debris flow erosion and sedimentation patterns. The study is based on detailed near-surface mapping of a 1900 km² 3D seismic volume from the southern Magdalena Fan, offshore Colombia. The study area is characterized by two NE-trending anticlines that form the northern tip of the Southern Sinú Fold Belt. In front of the structures, a 200 m thick MTC overlies an erosional surface. The horizons interpreted as the top and base of the deposit can be continuously mapped across the study area; however, grooves on the basal shear surface reveal three transport directions linked to separate headwalls along the frontal fringe of the fold belt, and thus indicate the coalescence of several flow events into a composite MTC. Here we focus on the central MTC, which can be traced updip across the northern plunge of the southern anticline to the steep frontal limb of another structure at the edge of the data set. The emplacing flow initially trended NW, but was deflected to the SW upon encountering the back limb of the northern anticline. It changed trend again where it crossed the southern anticlinal structure through a narrow notch. Updip of this structure, the erosional relief is 500 m, and the deposit is 6 km wide, 100 m thick, and is composed of debrites and isolated blocks. As it traversed the structure, basal relief reduced to 250 m and the deposit, which is mainly composed of blocks, is only 40 m thick and 3 km wide. Downdip of the structures, the erosional surface widens to 16 km and is almost entirely filled by a 200 m thick unit composed of chaotic and folded reflectors and blocks. Here, the crest of an underlying levee directed the flow to the SW and is overlain by blocks aligned parallel to the direction of flow. The response of MTCs to underlying bathymetry can be reflected in their flow pathways, erosional relief and in the characteristics of the deposits. The presence of blocks, internal deformation, changes in thickness and matrix content can all be influenced by the interaction between MTCs and irregular substrates. Panel_15242 Panel_15242 11:30 AM 11:50 AM

Panel_14467 Panel_14467 8:00 AM 11:50 AM

Panel_15814 Panel_15814 8:00 AM 12:00 AM

The Northwest European gas province is a mature area in which the production of gas from conventional reservoirs is declining. Unconventional tough gas reservoirs in low-net-to-gross stratigraphic intervals may constitute a secondary source of fossil energy to prolong the gas supply in the future. However, to date, production of these fine-grained, low-permeable reservoirs has been hampered by the economic risks related to the uncertainties in their size, shape, spatial distribution and reservoir properties. This research focusses on crevasse splay sediment bodies in fluvial floodplain intervals using data from Cenozoïc outcrop analogues from the Ebro and Tremp-Graus Basins in Spain and contemporary fluvial systems in the Altiplano Basin, Bolivia. The study aims to develop a thorough understanding of the underlying depositional mechanisms and their autogenic and allogenic controls. Furthermore, the resulting reservoir architecture is analysed and compared to observations made in the Triassic subsurface of the West Netherlands Basin, the Netherlands. Results show that individual crevasse splays have surface areas up to several square kilometres and thicknesses ranging from centimetre to decimetre scale. Their grain-size distribution comprises two main constituents: (1) a coarser component, deposited in a waning flow regime, and (2) a finer component, settled out from suspension in a standing body of flood water. Crevasse splays appear as vertically-stacked and laterally-amalgamated sheets in intervals up to several metres in thickness. These intervals show sand-on sand contact near their apex (levee breach point) and may be incised by the main fluvial channel after successful avulsion, forming large, interconnected volumes. Intervals of nested crevasse splays, typically overlying well developed paleosols, appear periodically both in outcrop and in the subsurface, indicating some level of allogenic control by climatic or base-level variations and providing a tie point for basin-scale correlation. This work will be used to assess the potential of crevasse splay sandstones as secondary reservoirs and to establish a predictive workflow for the development of such reservoirs in the Triassic, U. Permian and Carboniferous subsurface of the Netherlands. The Northwest European gas province is a mature area in which the production of gas from conventional reservoirs is declining. Unconventional tough gas reservoirs in low-net-to-gross stratigraphic intervals may constitute a secondary source of fossil energy to prolong the gas supply in the future. However, to date, production of these fine-grained, low-permeable reservoirs has been hampered by the economic risks related to the uncertainties in their size, shape, spatial distribution and reservoir properties. This research focusses on crevasse splay sediment bodies in fluvial floodplain intervals using data from Cenozoïc outcrop analogues from the Ebro and Tremp-Graus Basins in Spain and contemporary fluvial systems in the Altiplano Basin, Bolivia. The study aims to develop a thorough understanding of the underlying depositional mechanisms and their autogenic and allogenic controls. Furthermore, the resulting reservoir architecture is analysed and compared to observations made in the Triassic subsurface of the West Netherlands Basin, the Netherlands. Results show that individual crevasse splays have surface areas up to several square kilometres and thicknesses ranging from centimetre to decimetre scale. Their grain-size distribution comprises two main constituents: (1) a coarser component, deposited in a waning flow regime, and (2) a finer component, settled out from suspension in a standing body of flood water. Crevasse splays appear as vertically-stacked and laterally-amalgamated sheets in intervals up to several metres in thickness. These intervals show sand-on sand contact near their apex (levee breach point) and may be incised by the main fluvial channel after successful avulsion, forming large, interconnected volumes. Intervals of nested crevasse splays, typically overlying well developed paleosols, appear periodically both in outcrop and in the subsurface, indicating some level of allogenic control by climatic or base-level variations and providing a tie point for basin-scale correlation. This work will be used to assess the potential of crevasse splay sandstones as secondary reservoirs and to establish a predictive workflow for the development of such reservoirs in the Triassic, U. Permian and Carboniferous subsurface of the Netherlands. Panel_15306 Panel_15306 8:05 AM 8:25 AM

The Upper Triassic Chinle Formation (CF) contains diverse and abundant trace fossil associations (TFA) in clastic and carbonate deposits from numerous areas on the Colorado Plateau and Rocky Mountain region. The sedimentologic and stratigraphic succession of TFA serve as proxies to reconstruct the spatial and temporal changes in environments, landscapes, local and regional hydrology, and climate during CF deposition. At least one study to date has used multiple proxy data to propose that sedimentary facies, pedofacies, and TFA record latitudinal climatic conditions that CF deposition experienced from 5o to 30oN latitude. These relations can be used to interpret sedimentation rate, accommodation, paleosol formation, and landscape stability to construct a sequence stratigraphic framework for the continental deposits that have no marine influence on stratal architecture and stacking patterns. Deposits interpreted as active meandering and braided river channels contained little to no bioturbation; only short U-shaped (Arenicolites) and horizontal surface burrows (Planolites), trails (Cochlichnus, Gordia, Mermia, Haplotichnus), and rare footprints, reflecting periods of low flow or short-term subaerial exposure with wet surfaces. Deposits interpreted as subaerially exposed bars, levee, and crevasse splays show a range of ichnodiversity, bioturbation intensity, tiering, and pedogenesis depending on degree and frequency of sediment accumulation, length of time between depositional events, and water table position. Such traces as Steinichnus, Planolites, Palaeophycus, and shallow roots comprise shallow tiers in sand- to mudstone-dominated deposits, mostly under high soil moisture conditions. As time between events and water-table depth increases, paleosol development also increases in concert with the presence of such traces as Camborygma, Scoyenia, Celliforma, insect cocoons, Naktodemasis, Archeoentomichnus, and more complex and deeper rooting patterns; more common particularly in proximal and distal floodplain deposits. Finer grained deposits also occupy more distal environments when accommodation and the grain sizes were available. Well-developed paleosols represent relatively stable landscapes that could serve as sequence boundaries with lateral extent. Patterns in floodplain deposits from weakly to better developed paleosols infer changes in accommodation thru time; weaker equates to higher accommodation, whereas better equates to lower accommodation. The Upper Triassic Chinle Formation (CF) contains diverse and abundant trace fossil associations (TFA) in clastic and carbonate deposits from numerous areas on the Colorado Plateau and Rocky Mountain region. The sedimentologic and stratigraphic succession of TFA serve as proxies to reconstruct the spatial and temporal changes in environments, landscapes, local and regional hydrology, and climate during CF deposition. At least one study to date has used multiple proxy data to propose that sedimentary facies, pedofacies, and TFA record latitudinal climatic conditions that CF deposition experienced from 5o to 30oN latitude. These relations can be used to interpret sedimentation rate, accommodation, paleosol formation, and landscape stability to construct a sequence stratigraphic framework for the continental deposits that have no marine influence on stratal architecture and stacking patterns. Deposits interpreted as active meandering and braided river channels contained little to no bioturbation; only short U-shaped (Arenicolites) and horizontal surface burrows (Planolites), trails (Cochlichnus, Gordia, Mermia, Haplotichnus), and rare footprints, reflecting periods of low flow or short-term subaerial exposure with wet surfaces. Deposits interpreted as subaerially exposed bars, levee, and crevasse splays show a range of ichnodiversity, bioturbation intensity, tiering, and pedogenesis depending on degree and frequency of sediment accumulation, length of time between depositional events, and water table position. Such traces as Steinichnus, Planolites, Palaeophycus, and shallow roots comprise shallow tiers in sand- to mudstone-dominated deposits, mostly under high soil moisture conditions. As time between events and water-table depth increases, paleosol development also increases in concert with the presence of such traces as Camborygma, Scoyenia, Celliforma, insect cocoons, Naktodemasis, Archeoentomichnus, and more complex and deeper rooting patterns; more common particularly in proximal and distal floodplain deposits. Finer grained deposits also occupy more distal environments when accommodation and the grain sizes were available. Well-developed paleosols represent relatively stable landscapes that could serve as sequence boundaries with lateral extent. Patterns in floodplain deposits from weakly to better developed paleosols infer changes in accommodation thru time; weaker equates to higher accommodation, whereas better equates to lower accommodation. Panel_15303 Panel_15303 8:25 AM 8:45 AM

The Aptian Barbalha Formation record deposition in a fluvial and lacustrine environment accumulated in a sag basin developed during the early post-rift in the Araripe Basin, northeastern Brazil. The development of depositional sequences in this unit reflects variation in the accommodation-to-sediment supply (A/S) ratio. Two depositional sequences, showing an overall fining-upward trend, are preserved within the succession. The sequences are bounded by regional subaerial unconformities formed during negative A/S ratio, and may be subdivided in Low-accommodation Systems Tracts (LAST) (positive A/S ratio close to zero) and High accommodation Systems Tracts (HAST) (A/S ratio between 0.5 and 1). Variation in A/S ratios must be related to tectonic subsidence and uplift of the basin, despite the post-rift setting. Sequence 1 is characterized by amalgamated, multistorey and multilateral, braided fluvial channel sandbodies, defining a LAST. These are interlayered with crevasse splay and floodplain deposits towards the top, passing to open lacustrine deposits, defining a HAST. The end of the first fining-upward cycle is marked by organic-rich shales interbedded with microbial carbonate laminae, coprolites, ostracodes, fish remains and carbonaceous plant debris. The thin (< 10 m thick), laterally persistent black shales are a significant marker in the basin. Total organic carbon in these shales is up to 24 wt.%, and they are correlative to organic-rich layers in the Ceará and in the Potiguar Basins, comprising potentially important source rocks. Sequence 2 overlies the organic-rich lacustrine deposits. At the base, this sequence is composed of amalgamated, multistorey and multilateral braided fluvial channel sandbodies (LAST), similar to Sequence 1, overlain by anastomosed fluvial deposits capped by lacustrine deposits, both grouped in a HAST. The second lacustrine cycle culminated with the precipitation of laminated (“papery”), micritic limestones of the Crato Member (basal Santana Formation). Paleocurrent data on fluvial deposits of sequences 1 and 2 shows a consistent pattern indicating paleoflow to the SE. Sedimentological evidence indicates humid to sub-humid climatic conditions during deposition of sequences 1 and 2. The Aptian Barbalha Formation record deposition in a fluvial and lacustrine environment accumulated in a sag basin developed during the early post-rift in the Araripe Basin, northeastern Brazil. The development of depositional sequences in this unit reflects variation in the accommodation-to-sediment supply (A/S) ratio. Two depositional sequences, showing an overall fining-upward trend, are preserved within the succession. The sequences are bounded by regional subaerial unconformities formed during negative A/S ratio, and may be subdivided in Low-accommodation Systems Tracts (LAST) (positive A/S ratio close to zero) and High accommodation Systems Tracts (HAST) (A/S ratio between 0.5 and 1). Variation in A/S ratios must be related to tectonic subsidence and uplift of the basin, despite the post-rift setting. Sequence 1 is characterized by amalgamated, multistorey and multilateral, braided fluvial channel sandbodies, defining a LAST. These are interlayered with crevasse splay and floodplain deposits towards the top, passing to open lacustrine deposits, defining a HAST. The end of the first fining-upward cycle is marked by organic-rich shales interbedded with microbial carbonate laminae, coprolites, ostracodes, fish remains and carbonaceous plant debris. The thin (< 10 m thick), laterally persistent black shales are a significant marker in the basin. Total organic carbon in these shales is up to 24 wt.%, and they are correlative to organic-rich layers in the Ceará and in the Potiguar Basins, comprising potentially important source rocks. Sequence 2 overlies the organic-rich lacustrine deposits. At the base, this sequence is composed of amalgamated, multistorey and multilateral braided fluvial channel sandbodies (LAST), similar to Sequence 1, overlain by anastomosed fluvial deposits capped by lacustrine deposits, both grouped in a HAST. The second lacustrine cycle culminated with the precipitation of laminated (“papery”), micritic limestones of the Crato Member (basal Santana Formation). Paleocurrent data on fluvial deposits of sequences 1 and 2 shows a consistent pattern indicating paleoflow to the SE. Sedimentological evidence indicates humid to sub-humid climatic conditions during deposition of sequences 1 and 2. Panel_15304 Panel_15304 8:45 AM 9:05 AM

Standard models for initiation of continental rifting show normal faults nucleating and growing to form isolated hangingwall depocentres that enlarge and merge due to lateral fault propagation and linkage. Sedimentation rates are usually higher or equal to accommodation during the early, pre-linkage phase with footwall-derived consequent drainage systems supplying fluvial to lacustrine sediments. However, these models do not consider the impact of antecedent river systems on facies and thickness distribution in early rifts. Stratigraphic and sedimentological analysis of the Pliocene-Recent Corinth rift are here used to understand the architecture of early rift alluvial/fluvial systems from source to sink. In the northern Peloponnese, these are preserved in a series of uplifted E-W normal fault blocks incised by present-day north-flowing rivers. By correlation of fluvial successions across normal fault blocks, we propose a new sedimentary model for early rifting. The use of magnetostratigraphy and the determination of burial age using cosmonuclides 26Al/10Be give temporal constraints along four logs. The early rift fining-upward succession thickens and fines from west to east across normal fault blocks. A basal conglomeratic unit infilled an inherited paleotopography. Palaeocurrent and sedimentological data indicate that an antecedent drainage system provided high sediment supply since the onset of rifting. Fluvial sediments were deposited by a NE-flowing low sinuosity gravel-braided river system. Earliest normal faults are sealed by syn-rift sediments as displacement became focused on larger normal faults (15-20 km long, across-strike spacing of >4 km). Little or no consequent sediment supply has been detected and therefore significant footwall relief was not created during early rifting. Spatial variability of facies records displacement gradients along faults. For example, coarse alluvial conglomerates tend to occur in the centre of hangingwall depocentres while finer floodplain deposits accumulated along strike. At the rift scale, however, normal fault distribution and activity do not solely control facies distribution, being overwhelmed by high sediment discharge of the antecedent river. We develop a tectono-sedimentary model of normal fault growth and potential fluvial-lacustine reservoir distribution in early rifts with high S:A ratios that involve antecedent drainage systems and distributed normal faulting. Standard models for initiation of continental rifting show normal faults nucleating and growing to form isolated hangingwall depocentres that enlarge and merge due to lateral fault propagation and linkage. Sedimentation rates are usually higher or equal to accommodation during the early, pre-linkage phase with footwall-derived consequent drainage systems supplying fluvial to lacustrine sediments. However, these models do not consider the impact of antecedent river systems on facies and thickness distribution in early rifts. Stratigraphic and sedimentological analysis of the Pliocene-Recent Corinth rift are here used to understand the architecture of early rift alluvial/fluvial systems from source to sink. In the northern Peloponnese, these are preserved in a series of uplifted E-W normal fault blocks incised by present-day north-flowing rivers. By correlation of fluvial successions across normal fault blocks, we propose a new sedimentary model for early rifting. The use of magnetostratigraphy and the determination of burial age using cosmonuclides 26Al/10Be give temporal constraints along four logs. The early rift fining-upward succession thickens and fines from west to east across normal fault blocks. A basal conglomeratic unit infilled an inherited paleotopography. Palaeocurrent and sedimentological data indicate that an antecedent drainage system provided high sediment supply since the onset of rifting. Fluvial sediments were deposited by a NE-flowing low sinuosity gravel-braided river system. Earliest normal faults are sealed by syn-rift sediments as displacement became focused on larger normal faults (15-20 km long, across-strike spacing of >4 km). Little or no consequent sediment supply has been detected and therefore significant footwall relief was not created during early rifting. Spatial variability of facies records displacement gradients along faults. For example, coarse alluvial conglomerates tend to occur in the centre of hangingwall depocentres while finer floodplain deposits accumulated along strike. At the rift scale, however, normal fault distribution and activity do not solely control facies distribution, being overwhelmed by high sediment discharge of the antecedent river. We develop a tectono-sedimentary model of normal fault growth and potential fluvial-lacustine reservoir distribution in early rifts with high S:A ratios that involve antecedent drainage systems and distributed normal faulting. Panel_15308 Panel_15308 9:05 AM 9:25 AM

Panel_15815 Panel_15815 9:25 AM 12:00 AM

This paper is a synthesis of 52 modern and ancient examples of monsoonal and subtropical river systems, including 4 original field datasets. Monsoon rain is the main surface water supply to many of the world’s rivers. Some such rivers occur completely within the tropical monsoon climate zone, whereas others have parts of their drainages in temperate climate zones, or on high elevations and receive some of their water discharge from snow melt. Yet others, have their upstream drainages in the tropical monsoon climates, but flow through subtropical drylands. Some rivers in sub-humid to arid subtropics are ephemeral and receive monsoon rain and transmit discharge only during abnormal or strengthened monsoon seasons and the associated cyclonic flow. Common to all these rivers is that they frequently experience high-magnitude floods that last from just hours to months, with a yearly (seasonal) to decadal (ephemeral) recurrence frequency. The high-magnitude floods are caused by intense monsoonal rainfall events that may contain most of the annual precipitation. Rivers may transmit lower magnitude flood or non-flood discharges during the rest of the year or the rest of the monsoon season, or the river beds may remain dry for the most of the year, or even for a decade. These rivers distinctly contrast with perennial rivers, where the annual discharge range (highest-lowest discharge) is relatively small compared to its annual discharge mean. Some monsoonal rivers have discharges 40–50 times greater during the summer monsoon. It is this highly seasonal discharge with a characteristically rapid rise, sharp peak and rapid decline of the flood hydrographs that define the monsoonal and sub-tropical river form and function, as well as the facies and facies successions, as up to 85-95% of their annual sediment transport and deposition occurs during these events. The paper presents specific recognition criteria that differentiate the highly seasonal river deposits from perennial river facies models. The internal variability within the highly seasonal rivers is presented as a continuum with end members. The monsoon regions, and the bordering subtropical regions reside on each side of the equatorial perennial rainfall regions, approximately between ca 10-35° N and S. However, multiple greenhouse world examples occur at considerably higher latitudes, suggesting hydrological cycle, poleward moisture transport and climate zones different from the current ice-house world. This paper is a synthesis of 52 modern and ancient examples of monsoonal and subtropical river systems, including 4 original field datasets. Monsoon rain is the main surface water supply to many of the world’s rivers. Some such rivers occur completely within the tropical monsoon climate zone, whereas others have parts of their drainages in temperate climate zones, or on high elevations and receive some of their water discharge from snow melt. Yet others, have their upstream drainages in the tropical monsoon climates, but flow through subtropical drylands. Some rivers in sub-humid to arid subtropics are ephemeral and receive monsoon rain and transmit discharge only during abnormal or strengthened monsoon seasons and the associated cyclonic flow. Common to all these rivers is that they frequently experience high-magnitude floods that last from just hours to months, with a yearly (seasonal) to decadal (ephemeral) recurrence frequency. The high-magnitude floods are caused by intense monsoonal rainfall events that may contain most of the annual precipitation. Rivers may transmit lower magnitude flood or non-flood discharges during the rest of the year or the rest of the monsoon season, or the river beds may remain dry for the most of the year, or even for a decade. These rivers distinctly contrast with perennial rivers, where the annual discharge range (highest-lowest discharge) is relatively small compared to its annual discharge mean. Some monsoonal rivers have discharges 40–50 times greater during the summer monsoon. It is this highly seasonal discharge with a characteristically rapid rise, sharp peak and rapid decline of the flood hydrographs that define the monsoonal and sub-tropical river form and function, as well as the facies and facies successions, as up to 85-95% of their annual sediment transport and deposition occurs during these events. The paper presents specific recognition criteria that differentiate the highly seasonal river deposits from perennial river facies models. The internal variability within the highly seasonal rivers is presented as a continuum with end members. The monsoon regions, and the bordering subtropical regions reside on each side of the equatorial perennial rainfall regions, approximately between ca 10-35° N and S. However, multiple greenhouse world examples occur at considerably higher latitudes, suggesting hydrological cycle, poleward moisture transport and climate zones different from the current ice-house world. Panel_15305 Panel_15305 10:10 AM 10:30 AM

The PETM interval in the Bighorn Basin provides a remarkable record of changes in the fluvial sedimentary record that can be tied to a high resolution climate record. The trends suggest that climate changes significantly influenced stratigraphic architecture in the northern Bighorn Basin. The middle 20m of the PETM is characterized by unusual deposits relative to the stratigraphic sections above and below: thick, welded paleosols in some locations and an abnormally thick channel-belt sandstone lateral to the welded paleosols. Comparison to the climate record, reconstructed qualitatively and quantitatively from paleosols, indicates that changes in alluvial architecture during the PETM are associated with overall drier conditions. In particular, the thick welded paleosols correspond to times when floodplains were well drained and mean annual precipitation (MAP) was reduced. Stratigraphic intervals below and above the main part of the PETM interval are dominated by thin paleosols, widely separated by thick avulsion deposits. Those intervals correspond to times of wetter floodplains and higher MAP. Paleosol complexity and spacing suggest that sediment flux to the basin varied due to precipitation fluctuations associated with PETM warming. Reduced floodplain accretion during the middle PETM indicates that sediment supply from the surrounding Laramide mountain ranges diminished in response to drier climates. Sediment supply depends on the balance between sediment availability and transport efficiency. We hypothesize that drier episodes caused reduced vegetation cover in source areas. Diminished plant cover promotes erosion and sediment yield by decreasing water infiltration and exposing more soil to overland flows. But, because precipitation was reduced, much of that sediment was stored in upstream reaches of the fluvial system rather than moving to the depositional basin. Welded paleosols formed because of diminished sediment supply, which caused lower accretion rates. With a return to wetter conditions after the middle PETM, upstream water flux increased, stored sediment was flushed to downstream areas, where rivers developed more prominent alluvial ridges, and avulsion/splay deposition on the floodplain was more common. Those intervals correspond to higher rates of accretion resulting in more widely spaced paleosols and thicker avulsion deposits. Our results show how paleosols provide information on the fluvial response to climate change. The PETM interval in the Bighorn Basin provides a remarkable record of changes in the fluvial sedimentary record that can be tied to a high resolution climate record. The trends suggest that climate changes significantly influenced stratigraphic architecture in the northern Bighorn Basin. The middle 20m of the PETM is characterized by unusual deposits relative to the stratigraphic sections above and below: thick, welded paleosols in some locations and an abnormally thick channel-belt sandstone lateral to the welded paleosols. Comparison to the climate record, reconstructed qualitatively and quantitatively from paleosols, indicates that changes in alluvial architecture during the PETM are associated with overall drier conditions. In particular, the thick welded paleosols correspond to times when floodplains were well drained and mean annual precipitation (MAP) was reduced. Stratigraphic intervals below and above the main part of the PETM interval are dominated by thin paleosols, widely separated by thick avulsion deposits. Those intervals correspond to times of wetter floodplains and higher MAP. Paleosol complexity and spacing suggest that sediment flux to the basin varied due to precipitation fluctuations associated with PETM warming. Reduced floodplain accretion during the middle PETM indicates that sediment supply from the surrounding Laramide mountain ranges diminished in response to drier climates. Sediment supply depends on the balance between sediment availability and transport efficiency. We hypothesize that drier episodes caused reduced vegetation cover in source areas. Diminished plant cover promotes erosion and sediment yield by decreasing water infiltration and exposing more soil to overland flows. But, because precipitation was reduced, much of that sediment was stored in upstream reaches of the fluvial system rather than moving to the depositional basin. Welded paleosols formed because of diminished sediment supply, which caused lower accretion rates. With a return to wetter conditions after the middle PETM, upstream water flux increased, stored sediment was flushed to downstream areas, where rivers developed more prominent alluvial ridges, and avulsion/splay deposition on the floodplain was more common. Those intervals correspond to higher rates of accretion resulting in more widely spaced paleosols and thicker avulsion deposits. Our results show how paleosols provide information on the fluvial response to climate change. Panel_15310 Panel_15310 10:30 AM 10:50 AM

Distributive Fluvial Systems (DFS) form the dominant geomorphic fluvial elements in modern continental sedimentary basins, thus we expect DFS deposits to comprise much of the fluvial rock record. Therefore, understanding geometries and distributions of channels and floodplains on modern DFS may provide valuable information on expected patterns of sediments in fluvial rocks. In our previous work, we hypothesized that rivers on DFS commonly decrease in size downfan. We are testing this hypothesis through evaluation of LANDSAT images of large DFS. In this preliminary study, we report on channel width for DFS in the Chaco Plain of the Andean Foreland Basin. We use ArcGIS to: (1) isolate regions that correspond to the active channel (e.g., exposed sand and water), (2) divide the active channel into equal segments of ~1000 m length, and (3) determine the area covered by the active channel in each segment. The mean active channel width is determined by dividing this area by the 1000m length for each stream segment. This work results in a graph that shows the change in channel width downfan from the apex every 1000m for each river system. For most rivers on DFS in the Chaco Plain, active channel width decreases downfan, thus supporting the hypothesis for this region. Several of the rivers (e.g., Rio Grande, Parapeti, and Pilcomayo) diminish in width to the point of termination in wetlands distal on the megafan. Though this method only shows widths of active channels and does not completely capture the channel-belt width, we expect the channel-belt width to remain relatively proportional to the width of the active channel. Thus, these results indicate that channel-belt sandstones should diminish in width distally in DFS deposits. Distributive Fluvial Systems (DFS) form the dominant geomorphic fluvial elements in modern continental sedimentary basins, thus we expect DFS deposits to comprise much of the fluvial rock record. Therefore, understanding geometries and distributions of channels and floodplains on modern DFS may provide valuable information on expected patterns of sediments in fluvial rocks. In our previous work, we hypothesized that rivers on DFS commonly decrease in size downfan. We are testing this hypothesis through evaluation of LANDSAT images of large DFS. In this preliminary study, we report on channel width for DFS in the Chaco Plain of the Andean Foreland Basin. We use ArcGIS to: (1) isolate regions that correspond to the active channel (e.g., exposed sand and water), (2) divide the active channel into equal segments of ~1000 m length, and (3) determine the area covered by the active channel in each segment. The mean active channel width is determined by dividing this area by the 1000m length for each stream segment. This work results in a graph that shows the change in channel width downfan from the apex every 1000m for each river system. For most rivers on DFS in the Chaco Plain, active channel width decreases downfan, thus supporting the hypothesis for this region. Several of the rivers (e.g., Rio Grande, Parapeti, and Pilcomayo) diminish in width to the point of termination in wetlands distal on the megafan. Though this method only shows widths of active channels and does not completely capture the channel-belt width, we expect the channel-belt width to remain relatively proportional to the width of the active channel. Thus, these results indicate that channel-belt sandstones should diminish in width distally in DFS deposits. Panel_15316 Panel_15316 10:50 AM 11:10 AM

Continental basin margins are commonly dominated by alluvial fan environments, which are long-lived throughout basin development. Fan deposition is influenced by: 1) varied transport and depositional mechanisms; 2) interactions between the fan and contemporaneous environments in the basin centre; 3) long-term allocyclic climatic variations; and, 4) localised autocyclic variations. Towards the distal extent of the basin, the alluvial fan interdigitates through a zone of interaction with contemporaneous environments in the basin centre. The sedimentology of the zone of interaction can have a significant impact upon basin-scale fluid flow by generating or restricting fluid migration pathways between the fan and permissible reservoir or seal lithologies in the basin centre. This work considers a well-exposed analogue for continental basin margin systems through the examination of the Cutler Group sediments of the Paradox Basin, western U.S.A. The work presents generalised spatial facies models across the Cutler Group alluvial fans and the zone of interaction. Temporal facies models have been constructed to highlight how long-term allocyclic climatic variations and short-term and localised autocyclic variations control deposition in the Cutler Group. The identified cyclicity highlights clear horizons which can be used to cyclostratigraphically correlate through the deposits, allowing for the further examination of basin-scale fluid migration pathways. The generic facies models derived from this work are applied to the basin margin sediments of the Permian Brockram Facies, of the East Irish Sea Basin, U.K. The application of the Cuter Group models provides significant insight into the sedimentology, geometry, and flow pathway connectivity of the Brockram Facies. This work highlights the impact of the deposits of both the alluvial fan and the zone of interaction on basin-scale fluid migration pathways and prospectivity in continental basins. The facies models show that basin margin sedimentation controls: 1) the connectivity of otherwise isolated potential reservoirs in the distal extent of the basin; 2) the development of ‘thief zones’ away from distal reservoirs; 3) the creation of bypass routes to charge distal reservoirs; and, 4) the introduction of baffles into an otherwise productive system. The net effect on fluid flow can be examined through the generation of a climate-based cyclostratigraphical framework. Continental basin margins are commonly dominated by alluvial fan environments, which are long-lived throughout basin development. Fan deposition is influenced by: 1) varied transport and depositional mechanisms; 2) interactions between the fan and contemporaneous environments in the basin centre; 3) long-term allocyclic climatic variations; and, 4) localised autocyclic variations. Towards the distal extent of the basin, the alluvial fan interdigitates through a zone of interaction with contemporaneous environments in the basin centre. The sedimentology of the zone of interaction can have a significant impact upon basin-scale fluid flow by generating or restricting fluid migration pathways between the fan and permissible reservoir or seal lithologies in the basin centre. This work considers a well-exposed analogue for continental basin margin systems through the examination of the Cutler Group sediments of the Paradox Basin, western U.S.A. The work presents generalised spatial facies models across the Cutler Group alluvial fans and the zone of interaction. Temporal facies models have been constructed to highlight how long-term allocyclic climatic variations and short-term and localised autocyclic variations control deposition in the Cutler Group. The identified cyclicity highlights clear horizons which can be used to cyclostratigraphically correlate through the deposits, allowing for the further examination of basin-scale fluid migration pathways. The generic facies models derived from this work are applied to the basin margin sediments of the Permian Brockram Facies, of the East Irish Sea Basin, U.K. The application of the Cuter Group models provides significant insight into the sedimentology, geometry, and flow pathway connectivity of the Brockram Facies. This work highlights the impact of the deposits of both the alluvial fan and the zone of interaction on basin-scale fluid migration pathways and prospectivity in continental basins. The facies models show that basin margin sedimentation controls: 1) the connectivity of otherwise isolated potential reservoirs in the distal extent of the basin; 2) the development of ‘thief zones’ away from distal reservoirs; 3) the creation of bypass routes to charge distal reservoirs; and, 4) the introduction of baffles into an otherwise productive system. The net effect on fluid flow can be examined through the generation of a climate-based cyclostratigraphical framework. Panel_15311 Panel_15311 11:10 AM 11:30 AM

The Upper Jurassic Norphlet Formation is a highly prospective conventional eolian sandstone reservoir target that overlies the Middle Jurassic Louann Salt in the Eastern Gulf of Mexico (EGOM); recent discoveries in the Norphlet play indicate reservoir quality is dependent upon the distribution and variability of eolian dune facies. We present a regional model of paleotransport for Norphlet erg sands based on from the integration of seismic, well log, and sedimentary petrology data from the EGOM. The results indicate the proximal Norphlet erg paleogeography included structural highs with 1000’s of feet of relief. Compositional and textural maturity of Norphlet erg sandstones increase away from these paleo-highs, indicating these paleohighs contributed sediment to the Norphlet erg. In addition, several alluvial, fluvial and wadi terrestrial depositional systems were routed toward through NE-SW oriented early Mesozoic rift graben systems into the proto-EGOM. As a result of NE-SW net sediment transport, the developing NW-SE oriented Norphlet erg exhibits an along-strike variability in provenance. In the Mississippi Interior Salt basin southeastward toward Mobile Bay, sediment input was entirely derived from Laurentian sources. In onshore southeastern Alabama, onshore Florida panhandle and offshore Florida, the provenance signature shows mixing of Laurentian and Gondwanan sources, and the proportion of Gondwanan input increases toward the Destin Dome and Pensacola federal lease blocks in the Apalachicola Embayment. This variability in provenance influences sandstone framework grain composition and abundances of labile accessory phases. Where these NE-SW oriented transport systems terminate, S-oriented winds in the Mississippi-Alabama region and W to NW-oriented winds in the Florida region reworked sediment locally into thick accumulations of eolian sands, with little mixing of sediment within the erg system. The down-dip limit was likely a pinch-out of the eolian system controlled by both sediment availability and eolian transport capacity; this model predicts that there is no shoreline facies that grade laterally with distal Norphlet erg sands but instead the basal facies of the Smackover Formation would onlap Norphlet erg sands during the incursion of the Oxfordian marine transgression into the EGOM. The Upper Jurassic Norphlet Formation is a highly prospective conventional eolian sandstone reservoir target that overlies the Middle Jurassic Louann Salt in the Eastern Gulf of Mexico (EGOM); recent discoveries in the Norphlet play indicate reservoir quality is dependent upon the distribution and variability of eolian dune facies. We present a regional model of paleotransport for Norphlet erg sands based on from the integration of seismic, well log, and sedimentary petrology data from the EGOM. The results indicate the proximal Norphlet erg paleogeography included structural highs with 1000’s of feet of relief. Compositional and textural maturity of Norphlet erg sandstones increase away from these paleo-highs, indicating these paleohighs contributed sediment to the Norphlet erg. In addition, several alluvial, fluvial and wadi terrestrial depositional systems were routed toward through NE-SW oriented early Mesozoic rift graben systems into the proto-EGOM. As a result of NE-SW net sediment transport, the developing NW-SE oriented Norphlet erg exhibits an along-strike variability in provenance. In the Mississippi Interior Salt basin southeastward toward Mobile Bay, sediment input was entirely derived from Laurentian sources. In onshore southeastern Alabama, onshore Florida panhandle and offshore Florida, the provenance signature shows mixing of Laurentian and Gondwanan sources, and the proportion of Gondwanan input increases toward the Destin Dome and Pensacola federal lease blocks in the Apalachicola Embayment. This variability in provenance influences sandstone framework grain composition and abundances of labile accessory phases. Where these NE-SW oriented transport systems terminate, S-oriented winds in the Mississippi-Alabama region and W to NW-oriented winds in the Florida region reworked sediment locally into thick accumulations of eolian sands, with little mixing of sediment within the erg system. The down-dip limit was likely a pinch-out of the eolian system controlled by both sediment availability and eolian transport capacity; this model predicts that there is no shoreline facies that grade laterally with distal Norphlet erg sands but instead the basal facies of the Smackover Formation would onlap Norphlet erg sands during the incursion of the Oxfordian marine transgression into the EGOM. Panel_15307 Panel_15307 11:30 AM 11:50 AM

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Panel_15816 Panel_15816 8:00 AM 12:00 AM

The origin of locally high porosity in carbonate reservoirs is still a matter of debate. One hypothetical concept is the late diagenetic calcite dissolution caused by acidic corrosive fluids (ACF) which migrated through the reservoir immediately before the actual oil phase. Our hydrogeochemical 1D-reactive mass transport (1DRT) modeling aims to test this concept by providing quantitative evidence based on the principles of chemical equilibrium thermodynamics and reactive mass transport. Such 1DRT calculations link 1D-purely advective pore water flow with the equilibrium thermodynamics of water-rock-gas interactions. Our motivation comes from the work of Ehrenberg et al. (2012) about dissolution of micritic calcite in Middle East oil fields and from their conclusions that (1) “diagenetic reactions must be constrained geochemically”, and (2) that “the theory about dissolution by acid pore water has produced significant net increases in bulk porosity has not been supported by models of mineral solubility and fluid flow”. Our modeling results reveal that the calcite solubility in the system “ACF/calcite/CO2(g)” increases along with decreasing pressure/temperature. During their migration, ACF may reach saturation with respect to calcite (e.g., at 305 atm and 85°C) before they enter the carbonate reservoir. Although saturated with respect to calcite, further migration of such ACF through the reservoir into areas of lower pressure/temperature (e.g., 295 atm and 82°C) causes undersaturation of ACF with respect to calcite. Consequently, such migrating ACF dissolve calcite until the saturation is re-established again (e.g., 295 atm and 82°C). Thus, thermodynamically controlled and repeated chemical re-equilibration among ACF, calcite, and CO2(g) during ACF migration from higher to lower pressure/temperature conditions is the driving force for continuous calcite dissolution. This continuous calcite dissolution along the flow path of ACF is the inevitable consequence of the chemical-thermodynamic behavior of the system “ACF/calcite/CO2(g)” under decreasing pressure/temperature –at least in the modeled p/T range from 295 atm/82°C to 205 atm/55°C. This holds also true for dolomitic reservoir rocks. Such self-propagating calcite dissolution before or during migration of the oil phase can increase reservoir porosity and permeability to a certain extent. In contrast, intense ACF-induced calcite dissolution may also lead to a local structural breakdown of the calcite matrix. The origin of locally high porosity in carbonate reservoirs is still a matter of debate. One hypothetical concept is the late diagenetic calcite dissolution caused by acidic corrosive fluids (ACF) which migrated through the reservoir immediately before the actual oil phase. Our hydrogeochemical 1D-reactive mass transport (1DRT) modeling aims to test this concept by providing quantitative evidence based on the principles of chemical equilibrium thermodynamics and reactive mass transport. Such 1DRT calculations link 1D-purely advective pore water flow with the equilibrium thermodynamics of water-rock-gas interactions. Our motivation comes from the work of Ehrenberg et al. (2012) about dissolution of micritic calcite in Middle East oil fields and from their conclusions that (1) “diagenetic reactions must be constrained geochemically”, and (2) that “the theory about dissolution by acid pore water has produced significant net increases in bulk porosity has not been supported by models of mineral solubility and fluid flow”. Our modeling results reveal that the calcite solubility in the system “ACF/calcite/CO₂(g)” increases along with decreasing pressure/temperature. During their migration, ACF may reach saturation with respect to calcite (e.g., at 305 atm and 85°C) before they enter the carbonate reservoir. Although saturated with respect to calcite, further migration of such ACF through the reservoir into areas of lower pressure/temperature (e.g., 295 atm and 82°C) causes undersaturation of ACF with respect to calcite. Consequently, such migrating ACF dissolve calcite until the saturation is re-established again (e.g., 295 atm and 82°C). Thus, thermodynamically controlled and repeated chemical re-equilibration among ACF, calcite, and CO₂(g) during ACF migration from higher to lower pressure/temperature conditions is the driving force for continuous calcite dissolution. This continuous calcite dissolution along the flow path of ACF is the inevitable consequence of the chemical-thermodynamic behavior of the system “ACF/calcite/CO₂(g)” under decreasing pressure/temperature –at least in the modeled p/T range from 295 atm/82°C to 205 atm/55°C. This holds also true for dolomitic reservoir rocks. Such self-propagating calcite dissolution before or during migration of the oil phase can increase reservoir porosity and permeability to a certain extent. In contrast, intense ACF-induced calcite dissolution may also lead to a local structural breakdown of the calcite matrix. Panel_15096 Panel_15096 8:05 AM 8:25 AM

Diagenesis is a major control on the petrophysical properties of carbonate reservoir rocks. Numerical simulation that uses information from core observations and measurements, diagenetic studies and a structural analysis of the basin development, is used to estimate these diagenetically-altered petrophysical properties away from well/cores out into the reservoir. Heat and fluid-flux simulations informed by both geomechanical and basin system analysis (basin modelling) simulations were applied to an offshore carbonate reservoir. This reservoir has been dolomitised during burial and has a complex permeability distribution that does not have an obvious depositional relationship. Basin modelling establishes the geological framework, the background state of rock compaction and the thermal state with time. The geomechanical simulation uses the appropriate geometry, rock properties and mechanical (tectonic) loads for the time of interest. It depicts fault-zone rock damage which locally creates potential flow pathways, depending on the distribution of the dilation and compaction zones within the fault zone. The conjecture is that fluid convection associated with the fault zone perturbs the temperature distribution and may introduce magnesium by fluid flow. This concept is tested by the heat- and fluid-flux simulations. The analysis provides a sequence of geometries, evolved rock mechanical properties, plus fluid and heat-flow patterns that allow us to infer the causes and consequences of the dolomitisation event affecting this reservoir. This workflow is generic and can be applied to any carbonate reservoir to enhance understanding of the relationship between fault-zones (i.e. dilation and compaction distributions) and fluid-related heat and solute transport in order to understand the diagenetic history of the reservoir and the resulting porosity and permeability distribution. Diagenesis is a major control on the petrophysical properties of carbonate reservoir rocks. Numerical simulation that uses information from core observations and measurements, diagenetic studies and a structural analysis of the basin development, is used to estimate these diagenetically-altered petrophysical properties away from well/cores out into the reservoir. Heat and fluid-flux simulations informed by both geomechanical and basin system analysis (basin modelling) simulations were applied to an offshore carbonate reservoir. This reservoir has been dolomitised during burial and has a complex permeability distribution that does not have an obvious depositional relationship. Basin modelling establishes the geological framework, the background state of rock compaction and the thermal state with time. The geomechanical simulation uses the appropriate geometry, rock properties and mechanical (tectonic) loads for the time of interest. It depicts fault-zone rock damage which locally creates potential flow pathways, depending on the distribution of the dilation and compaction zones within the fault zone. The conjecture is that fluid convection associated with the fault zone perturbs the temperature distribution and may introduce magnesium by fluid flow. This concept is tested by the heat- and fluid-flux simulations. The analysis provides a sequence of geometries, evolved rock mechanical properties, plus fluid and heat-flow patterns that allow us to infer the causes and consequences of the dolomitisation event affecting this reservoir. This workflow is generic and can be applied to any carbonate reservoir to enhance understanding of the relationship between fault-zones (i.e. dilation and compaction distributions) and fluid-related heat and solute transport in order to understand the diagenetic history of the reservoir and the resulting porosity and permeability distribution. Panel_15091 Panel_15091 8:25 AM 8:45 AM

Aptian-Albian oceanic anoxic event (OAE1) is marked by four separate events of Corg deposition. The first two of these events (OAE1a and OAE1b) are global, and have been recorded from numerous platform and basinal settings. Much less is known about the Albian OAE1c and OAE1d, especially their expression within shallow-marine Tethyan platforms. This study focuses on the Albian OAE and stable carbon isotope record of the Croatian Adriatic platform, and is based on detailed bed-by-bed analysis of ~460-m-thick thick platform-interior sequence, coupled by d13C analysis of bulk carbonate matrix of samples collected at 1-meter intervals. The Albian supersequence has 4 third-order depositional sequences bounded by breccia sequence boundaries; each sequence is characterized by cyclic carbonates. Fenestral caps to cycles predominate in the lower part of the succession. This suggests that moderately humid conditions initially inhibited development of microbial laminites, which become more abundant near the top of the Albian with drying. This is marked by increase in dolomitization and abundance of microbial laminite caps to parasequences. The mean values for d13C are +0.55‰ VPDB. The base of the Albian sequence Alb1 corresponds to the OAE1b and is characterized by a stepwise negative excursion of d13C, reaching a minimum value of -6.52‰ VPDB. Sequence Alb2 begins with a positive d13C excursion, followed by d13C values varying within the range of -6.52‰ to +2.19 ‰ VPDB; Sequence Alb3 represents a period of low d13C values, with the minimum value of -5.54 ‰ PDB. Sequence Alb4 encompasses both the highest and lowest values of d13C within the Upper Albian part of the supersequence, +2.19‰ and -4.77‰ PDB, respectively. The stable carbon isotope profiles of shallow-marine carbonates from the Croatian Adriatic platform show only a vague similarity with those from Tethyan pelagic sections, suggesting diagenetic overprint. This is particularly evident for subaerially exposed parts of the succession and massive crystalline dolomites, where carbonate-isotope values show highly depleted values. There is a general trend to lighter d13C values towards the end of Albian, as evident by preliminary correlation of OAE1d. Carbon has larger excursions from the mean during the OAE1b in the Early Albian and again in the Late Albian post-OAE1d event. The study shows that Albian OAEs exhibit no characteristic sedimentary record within the platform-interior succession. Aptian-Albian oceanic anoxic event (OAE1) is marked by four separate events of Corg deposition. The first two of these events (OAE1a and OAE1b) are global, and have been recorded from numerous platform and basinal settings. Much less is known about the Albian OAE1c and OAE1d, especially their expression within shallow-marine Tethyan platforms. This study focuses on the Albian OAE and stable carbon isotope record of the Croatian Adriatic platform, and is based on detailed bed-by-bed analysis of ~460-m-thick thick platform-interior sequence, coupled by d13C analysis of bulk carbonate matrix of samples collected at 1-meter intervals. The Albian supersequence has 4 third-order depositional sequences bounded by breccia sequence boundaries; each sequence is characterized by cyclic carbonates. Fenestral caps to cycles predominate in the lower part of the succession. This suggests that moderately humid conditions initially inhibited development of microbial laminites, which become more abundant near the top of the Albian with drying. This is marked by increase in dolomitization and abundance of microbial laminite caps to parasequences. The mean values for d13C are +0.55‰ VPDB. The base of the Albian sequence Alb1 corresponds to the OAE1b and is characterized by a stepwise negative excursion of d13C, reaching a minimum value of -6.52‰ VPDB. Sequence Alb2 begins with a positive d13C excursion, followed by d13C values varying within the range of -6.52‰ to +2.19 ‰ VPDB; Sequence Alb3 represents a period of low d13C values, with the minimum value of -5.54 ‰ PDB. Sequence Alb4 encompasses both the highest and lowest values of d13C within the Upper Albian part of the supersequence, +2.19‰ and -4.77‰ PDB, respectively. The stable carbon isotope profiles of shallow-marine carbonates from the Croatian Adriatic platform show only a vague similarity with those from Tethyan pelagic sections, suggesting diagenetic overprint. This is particularly evident for subaerially exposed parts of the succession and massive crystalline dolomites, where carbonate-isotope values show highly depleted values. There is a general trend to lighter d13C values towards the end of Albian, as evident by preliminary correlation of OAE1d. Carbon has larger excursions from the mean during the OAE1b in the Early Albian and again in the Late Albian post-OAE1d event. The study shows that Albian OAEs exhibit no characteristic sedimentary record within the platform-interior succession. Panel_15088 Panel_15088 8:45 AM 9:05 AM

Petrographic, geochemical, and fluid inclusion analyses of dolomite and calcite cements have been made on Mississippian carbonates collected from the surface and subsurface of the southern Midcontinent (Oklahoma, Missouri, Kansas and Arkansas). Limestone porosity is largely occluded by early marine and meteoric calcite cement. Fracture and vug porosity are filled with calcite, chert, and dolomite cements. Both early and late blocky ferroan calcite cements were formed in the deep phreatic zone. Saddle dolomite cements are late diagenetic, possibly related to the nearby Tri-State Mississippi Valley-type mineral district, which in turn is genetically associated with petroleum migration in the region. Carbon and oxygen isotope compositions of dolomite cements range from d18O(VPDB) = -2.7‰ to -7.7‰, and d13C(VPDB) = -0.4‰ to -2.1‰. Calcite cements range from d18O(VPDB) = -1.9 ‰ to -11‰, and d13C(VPDB) = 4.6‰ to -4.8‰. Isotope values are consistent with three diagenetic waters: meteoric water, seawater modified by meteoric water, and basinal water. Analysis of two-phase fluid inclusions (water and vapor) in late calcite and dolomite cements indicate the presence of both dilute and high salinity fluid end members (calculated values ranging from 0 to 25 equivalent weight % NaCl) at homogenization temperatures ranging from 57° to 170°C. These temperatures and salinities indicate a saline basinal fluid possibly mixing with a dilute fluid of meteoric or mixed seawater/meteoric origin. Elevated fluid inclusion temperatures over a broad region, not just in the mineral district, imply that the thermal maturity of Mississippian carbonate rocks may be higher than previously believed. This study indicates that the Mississippian carbonate resource play on the southern Midcontinent has a very complex diagenetic history, continuing long after early diagenetic cementation. Possibly the most important, and the least understood, diagenetic events affecting these rocks occurred during burial and basinal fluid migration through these strata. Extension of this study into north central Oklahoma will provide a better understanding of the porosity development (cementation history) and thermal maturity of Mississippian carbonate reservoirs in this area and should lead to more effective exploration strategies. Petrographic, geochemical, and fluid inclusion analyses of dolomite and calcite cements have been made on Mississippian carbonates collected from the surface and subsurface of the southern Midcontinent (Oklahoma, Missouri, Kansas and Arkansas). Limestone porosity is largely occluded by early marine and meteoric calcite cement. Fracture and vug porosity are filled with calcite, chert, and dolomite cements. Both early and late blocky ferroan calcite cements were formed in the deep phreatic zone. Saddle dolomite cements are late diagenetic, possibly related to the nearby Tri-State Mississippi Valley-type mineral district, which in turn is genetically associated with petroleum migration in the region. Carbon and oxygen isotope compositions of dolomite cements range from d18O(VPDB) = -2.7‰ to -7.7‰, and d13C(VPDB) = -0.4‰ to -2.1‰. Calcite cements range from d18O(VPDB) = -1.9 ‰ to -11‰, and d13C(VPDB) = 4.6‰ to -4.8‰. Isotope values are consistent with three diagenetic waters: meteoric water, seawater modified by meteoric water, and basinal water. Analysis of two-phase fluid inclusions (water and vapor) in late calcite and dolomite cements indicate the presence of both dilute and high salinity fluid end members (calculated values ranging from 0 to 25 equivalent weight % NaCl) at homogenization temperatures ranging from 57° to 170°C. These temperatures and salinities indicate a saline basinal fluid possibly mixing with a dilute fluid of meteoric or mixed seawater/meteoric origin. Elevated fluid inclusion temperatures over a broad region, not just in the mineral district, imply that the thermal maturity of Mississippian carbonate rocks may be higher than previously believed. This study indicates that the Mississippian carbonate resource play on the southern Midcontinent has a very complex diagenetic history, continuing long after early diagenetic cementation. Possibly the most important, and the least understood, diagenetic events affecting these rocks occurred during burial and basinal fluid migration through these strata. Extension of this study into north central Oklahoma will provide a better understanding of the porosity development (cementation history) and thermal maturity of Mississippian carbonate reservoirs in this area and should lead to more effective exploration strategies. Panel_15095 Panel_15095 9:05 AM 9:25 AM

Panel_15733 Panel_15733 9:25 AM 12:00 AM

Predicting the distribution of reservoir heterogeneities is important for the prediction of reservoir performance, essential both for hydrocarbon production and carbon dioxide storage. Reservoir heterogeneity is influenced by the nature and distribution of depositional facies, diagenetic products and structural elements, and these are presented as geobodies in subsurface modeling. We focus here on diagenetic geobodies, and to gain a better insight in the distribution and dimension of such geobodies, outcrop analogues are investigated. The current study presents research on dolomite geobodies in Picos de Europa (northern Spain). The goal is to develop a methodology to capture and present the distribution and dimension of diagenetic geobodies and to derive meaningful correlations, which could later be implemented in subsurface models. The documented geobodies occur in Carboniferous host rock of the so-called “Caliza de Montaña” (Barcaliente and Valdeteja Formations) and the Picos de Europa Formation. The study area is near Fuente Dé, the southern part of the Picos de Europa Province. Although terrestrial LIDAR scanning could provide more detailed 3D information on the geobodies, it would also come with a significant additional cost. Hence, we developed a methodology based on remote sensing data, complemented by field pictures, field GPS tracing and mapping and laser rangefinder and tape measurements. We propose new calculation methods to derive height and width of diagenetic bodies documented by laser rangefinder measurements of inaccessible cliff faces. Our results show that the dolomite bodies in the Picos de Europa Formation (recorded on hilly terrain) have a principal length axis oriented WNW-ESE, similar to the main faults in the area. A length/width ratio of 1.8 is apparent, whereas correlation between height and width is less pronounced. For the dolomite bodies in the Montaña beds (captured on steep cliff faces), length of the bodies could not be documented. No correlation was apparent between width and height of the bodies. Dimensions of the geobodies in the Montaña beds are significantly greater than those in the Picos de Europa Formation. Our findings on the dimensions are interpreted in the context of the fracture network, and thus the tectonic history, fluid flow, and depositional lithologies. This study is part of the Qatar Carbonates and Carbon Storage Centre funded jointly by Qatar Petroleum, Shell and the Qatar Science & Technology Park. Predicting the distribution of reservoir heterogeneities is important for the prediction of reservoir performance, essential both for hydrocarbon production and carbon dioxide storage. Reservoir heterogeneity is influenced by the nature and distribution of depositional facies, diagenetic products and structural elements, and these are presented as geobodies in subsurface modeling. We focus here on diagenetic geobodies, and to gain a better insight in the distribution and dimension of such geobodies, outcrop analogues are investigated. The current study presents research on dolomite geobodies in Picos de Europa (northern Spain). The goal is to develop a methodology to capture and present the distribution and dimension of diagenetic geobodies and to derive meaningful correlations, which could later be implemented in subsurface models. The documented geobodies occur in Carboniferous host rock of the so-called “Caliza de Montaña” (Barcaliente and Valdeteja Formations) and the Picos de Europa Formation. The study area is near Fuente Dé, the southern part of the Picos de Europa Province. Although terrestrial LIDAR scanning could provide more detailed 3D information on the geobodies, it would also come with a significant additional cost. Hence, we developed a methodology based on remote sensing data, complemented by field pictures, field GPS tracing and mapping and laser rangefinder and tape measurements. We propose new calculation methods to derive height and width of diagenetic bodies documented by laser rangefinder measurements of inaccessible cliff faces. Our results show that the dolomite bodies in the Picos de Europa Formation (recorded on hilly terrain) have a principal length axis oriented WNW-ESE, similar to the main faults in the area. A length/width ratio of 1.8 is apparent, whereas correlation between height and width is less pronounced. For the dolomite bodies in the Montaña beds (captured on steep cliff faces), length of the bodies could not be documented. No correlation was apparent between width and height of the bodies. Dimensions of the geobodies in the Montaña beds are significantly greater than those in the Picos de Europa Formation. Our findings on the dimensions are interpreted in the context of the fracture network, and thus the tectonic history, fluid flow, and depositional lithologies. This study is part of the Qatar Carbonates and Carbon Storage Centre funded jointly by Qatar Petroleum, Shell and the Qatar Science & Technology Park. Panel_15089 Panel_15089 10:10 AM 10:30 AM

The Mississippian Limestone in Oklahoma is a petroleum exploration target in northern Oklahoma and southern Kansas, and diagenetic events are a significant factor in controlling reservoir quality. In this study, petrographic, geochemical, and paleomagnetic data were used to determine the origin and timing of diagenetic events in five unoriented cores from northern Oklahoma. Petrographic analysis indicates a complex paragenetic sequence. Early diagenetic events include silica precipitation and dolomitization. Middle diagenetic events include brecciation, silica dissolution, fracturing, dolomitization, and silica precipitation, and are interpreted as resulting from subaerial exposure. Late diagenetic features, attributed to burial and hydrothermal fluid flow, include stylolitization, dissolution, and precipitation of megaquartz, calcite, sphalerite, pyrite, and baroque dolomite. The 87Sr/86Sr isotopic data for the limestone range from co-eval to radiogenic. Samples from the two cores which are located to the north and closer to the Tri-State MVT district contain the most elevated values. Thermal demagnetization removes a low temperature viscous remanent magnetization (VRM) and a chemical remanent magnetization (CRM) from 240 - 500°C that is interpreted to reside in magnetite. Rock magnetic studies confirm the magnetite interpretation. An attempt was made to orient the cores using the VRM but it resulted in a 300° streaked distribution of declinations with shallow inclinations, and as a result, was not successful. The inclinations of the CRM in the five cores are similar (mean = - 2.5°, ?95 = 1.4°, n = 270). The age of the CRM was determined by comparing the measured inclinations with the expected inclinations for the study area. This analysis indicates that the CRM was acquired in the Permian. This is consistent with the dates for mineralization in the nearby Tri-State MVT deposit and interpretations in other studies which hypothesize a Permian hydrothermal system. Burial remagnetization mechanisms such as maturation of organic matter or clay diagenesis are not likely because low organic matter and clay content. The age of the CRM and the evidence for hydrothermal alteration suggest that CRM acquisition was caused by external hydrothermal fluids. The Mississippian Limestone in Oklahoma is a petroleum exploration target in northern Oklahoma and southern Kansas, and diagenetic events are a significant factor in controlling reservoir quality. In this study, petrographic, geochemical, and paleomagnetic data were used to determine the origin and timing of diagenetic events in five unoriented cores from northern Oklahoma. Petrographic analysis indicates a complex paragenetic sequence. Early diagenetic events include silica precipitation and dolomitization. Middle diagenetic events include brecciation, silica dissolution, fracturing, dolomitization, and silica precipitation, and are interpreted as resulting from subaerial exposure. Late diagenetic features, attributed to burial and hydrothermal fluid flow, include stylolitization, dissolution, and precipitation of megaquartz, calcite, sphalerite, pyrite, and baroque dolomite. The 87Sr/86Sr isotopic data for the limestone range from co-eval to radiogenic. Samples from the two cores which are located to the north and closer to the Tri-State MVT district contain the most elevated values. Thermal demagnetization removes a low temperature viscous remanent magnetization (VRM) and a chemical remanent magnetization (CRM) from 240 - 500°C that is interpreted to reside in magnetite. Rock magnetic studies confirm the magnetite interpretation. An attempt was made to orient the cores using the VRM but it resulted in a 300° streaked distribution of declinations with shallow inclinations, and as a result, was not successful. The inclinations of the CRM in the five cores are similar (mean = - 2.5°, ?95 = 1.4°, n = 270). The age of the CRM was determined by comparing the measured inclinations with the expected inclinations for the study area. This analysis indicates that the CRM was acquired in the Permian. This is consistent with the dates for mineralization in the nearby Tri-State MVT deposit and interpretations in other studies which hypothesize a Permian hydrothermal system. Burial remagnetization mechanisms such as maturation of organic matter or clay diagenesis are not likely because low organic matter and clay content. The age of the CRM and the evidence for hydrothermal alteration suggest that CRM acquisition was caused by external hydrothermal fluids. Panel_15094 Panel_15094 10:30 AM 10:50 AM

The Goldsmith Clear Fork field was discovered in 1946 and has produced over 300 million barrels of oil from a thick carbonate section dominated by anhydritic dolomite with lesser limestone. Reservoir quality is low to moderate with a mixed pore network of interparticle and moldic megapores along with intercrystalline nanopores and micropores. The AMOCO #234 Goldsmith core was selected as the type core to define the origin of dolonanopores and dolomicropores and their characteristics. In thin section these pores are seen occurring in patches of the matrix, in peloids and clasts, and in fossils. These occurrences are similar to some examples of micropores networks observed in limestones. As seen on the SEM using Ar-ion milled samples, the nano- and micropores occur between crystals of dolomite that are euhedral and generally range in size from <400 nanometers to 5 microns. The crystals are poorly sorted relative to size. In general the pores are triangular in shape because they are positioned between euhedral crystals. The pores range from 20 nm to a few microns. Submicron diagenetic illite flakes commonly form in the pores further subdividing the pore. The nano-to microsized dolomite formed by replacement of matrix and grains and by precipitation into pore spaces. The resulting pore networks are quite varied. As an example, where the dolomite replaced former calcite microrhombic grains with associated micropores, the nano- and micropores mimic the former calcite micropore network. This is interpreted as a replacement process of microcrystalline rhombic calcite. In some fine peloidal dolopackstones, the peloids are replaced by a dense network of dolomite crystals with some triangular nanopores still present, while in the interpeloidal pores, some nano- to microdolomite crystals precipitated. The interpeloidal pores are small but appear to form a fair connected pore network. The porosities in the studies core are generally less than 15% and permeabilites are generally less than 10 md with most values less than 1 md. The recognition of nano- and micropores is important because they can be a major contributor to total porosity, while adding little to permeability. They also may affect reservoir saturation in that the megapores may be saturated with hydrocarbon whereas the finer pores are filled with water. Therefore, the quantity of nano- and micropores must be taken into consideration when calculating flow rates and field-wide reserves. The Goldsmith Clear Fork field was discovered in 1946 and has produced over 300 million barrels of oil from a thick carbonate section dominated by anhydritic dolomite with lesser limestone. Reservoir quality is low to moderate with a mixed pore network of interparticle and moldic megapores along with intercrystalline nanopores and micropores. The AMOCO #234 Goldsmith core was selected as the type core to define the origin of dolonanopores and dolomicropores and their characteristics. In thin section these pores are seen occurring in patches of the matrix, in peloids and clasts, and in fossils. These occurrences are similar to some examples of micropores networks observed in limestones. As seen on the SEM using Ar-ion milled samples, the nano- and micropores occur between crystals of dolomite that are euhedral and generally range in size from <400 nanometers to 5 microns. The crystals are poorly sorted relative to size. In general the pores are triangular in shape because they are positioned between euhedral crystals. The pores range from 20 nm to a few microns. Submicron diagenetic illite flakes commonly form in the pores further subdividing the pore. The nano-to microsized dolomite formed by replacement of matrix and grains and by precipitation into pore spaces. The resulting pore networks are quite varied. As an example, where the dolomite replaced former calcite microrhombic grains with associated micropores, the nano- and micropores mimic the former calcite micropore network. This is interpreted as a replacement process of microcrystalline rhombic calcite. In some fine peloidal dolopackstones, the peloids are replaced by a dense network of dolomite crystals with some triangular nanopores still present, while in the interpeloidal pores, some nano- to microdolomite crystals precipitated. The interpeloidal pores are small but appear to form a fair connected pore network. The porosities in the studies core are generally less than 15% and permeabilites are generally less than 10 md with most values less than 1 md. The recognition of nano- and micropores is important because they can be a major contributor to total porosity, while adding little to permeability. They also may affect reservoir saturation in that the megapores may be saturated with hydrocarbon whereas the finer pores are filled with water. Therefore, the quantity of nano- and micropores must be taken into consideration when calculating flow rates and field-wide reserves. Panel_15092 Panel_15092 10:50 AM 11:10 AM

Jurassic carbonate source rocks within the Jurassic Tuwaiq Mountain, Hanifa, and basal Jubaila formations supplied vast amounts of oil to Jurassic carbonate reservoirs. These source rocks contain 1% to 14% TOC, abundant organopores, and very low to no clay content. Deposition was in an outer ramp to basin depositional environment, beneath fair-weather wave base and within storm wave base. Storms swept sediment down-dip into the outer ramp/basin and appear to have waxed and waned in a cyclic manner. Sedimentary structures include: gently undulating parallel lamination (GUP lamination) or sinuous lamination; micro-hummocky cross lamination; ripple lamination; micro cut and fill lamination; and micro-topographic infill lamination. TOC appears to be concentrated in fecal pellets that were transported down-dip by storms. Three lithofacies have been recognized: 1) anoxic, black, laminated, wackestone to mud-dominated packstone; 2) dysoxic, black, horizontally micro-bioturbated, laminated to very thin bedded, wackestone to mud-dominated packstone; and 3) oxygenated, gray, bioturbated, thin bedded, wackestone to mud-dominated packstone. Fecal pellets are the most common grains. Skeletal constituents include: Bositra buchi bivalves that are whole, shell halves, and fragmented to highly fragmented; and abundant non-descript highly fragmented skeletal detritus. A pycnocline divided the water column into: 1) anoxic water beneath; 2) dysoxic water at the contact; and 3) oxygenated water above. The pycnocline moved up and down in the water column, creating apparent cyclicity within the strata, and may have been controlled by: relative sea level change; variable restriction of circulation; or a combination of both. Diagenetic products include: dolomite crystals (0% to 5%); anhydrite crystals (0% to 5%); pyrite cubes and finely disseminated crystals (1% to 3%). All of this data has been utilized to characterize and explore for unconventional Jurassic carbonate source rocks in Saudi Arabia. Jurassic carbonate source rocks within the Jurassic Tuwaiq Mountain, Hanifa, and basal Jubaila formations supplied vast amounts of oil to Jurassic carbonate reservoirs. These source rocks contain 1% to 14% TOC, abundant organopores, and very low to no clay content. Deposition was in an outer ramp to basin depositional environment, beneath fair-weather wave base and within storm wave base. Storms swept sediment down-dip into the outer ramp/basin and appear to have waxed and waned in a cyclic manner. Sedimentary structures include: gently undulating parallel lamination (GUP lamination) or sinuous lamination; micro-hummocky cross lamination; ripple lamination; micro cut and fill lamination; and micro-topographic infill lamination. TOC appears to be concentrated in fecal pellets that were transported down-dip by storms. Three lithofacies have been recognized: 1) anoxic, black, laminated, wackestone to mud-dominated packstone; 2) dysoxic, black, horizontally micro-bioturbated, laminated to very thin bedded, wackestone to mud-dominated packstone; and 3) oxygenated, gray, bioturbated, thin bedded, wackestone to mud-dominated packstone. Fecal pellets are the most common grains. Skeletal constituents include: Bositra buchi bivalves that are whole, shell halves, and fragmented to highly fragmented; and abundant non-descript highly fragmented skeletal detritus. A pycnocline divided the water column into: 1) anoxic water beneath; 2) dysoxic water at the contact; and 3) oxygenated water above. The pycnocline moved up and down in the water column, creating apparent cyclicity within the strata, and may have been controlled by: relative sea level change; variable restriction of circulation; or a combination of both. Diagenetic products include: dolomite crystals (0% to 5%); anhydrite crystals (0% to 5%); pyrite cubes and finely disseminated crystals (1% to 3%). All of this data has been utilized to characterize and explore for unconventional Jurassic carbonate source rocks in Saudi Arabia. Panel_15090 Panel_15090 11:10 AM 11:30 AM

Some carbonate grainstones have fitted fabrics that may form in the vadose zone and are therefore evidence for subaerial exposure. These grainstones may be composed of ooids, coated grains, skeletal grains or peloids. The grainstones have interlocking grains that fit together like puzzle pieces and could not possibly have formed that way during deposition. There is commonly isopachous rim cement surrounding the interlocking grains. The cement appears to have formed after the grains were fitted to each other but still fill a gap between the fitted grains. Examples of these fitted fabric grainstones have been identified in Devonian, Mississippian, Permian, Jurassic, Cretaceous, and modern strata of various parts of the world. This feature appears to be quite common if also commonly overlooked. It almost certainly occurs in carbonates throughout the geologic record. The fitted fabric was initially recognized and interpreted to be a result of vadose diagenesis by Dunham. Modern beachrock from the intertidal zone was noted to have grains that were more fitted to each other than grainstones forming in subtidal settings. Dissolution is interpreted to occur at grain contacts which over time flattens the contact and leads to the grains “fitting” to each other. There may be some pillars of undissolved material that preserve gaps between the grains that are later filled in with isopachous rim cement. The rocks have the appearance of being compacted and indeed this could be called “vadose compaction.” Burial compaction can be ruled out because there are few pressure solution features and the isopachous rim cement clearly postdates the fitting of the grains. Recognition of this important feature can help to identify cryptic exposure surfaces and sequence boundaries that otherwise might be difficult to recognize. Some carbonate grainstones have fitted fabrics that may form in the vadose zone and are therefore evidence for subaerial exposure. These grainstones may be composed of ooids, coated grains, skeletal grains or peloids. The grainstones have interlocking grains that fit together like puzzle pieces and could not possibly have formed that way during deposition. There is commonly isopachous rim cement surrounding the interlocking grains. The cement appears to have formed after the grains were fitted to each other but still fill a gap between the fitted grains. Examples of these fitted fabric grainstones have been identified in Devonian, Mississippian, Permian, Jurassic, Cretaceous, and modern strata of various parts of the world. This feature appears to be quite common if also commonly overlooked. It almost certainly occurs in carbonates throughout the geologic record. The fitted fabric was initially recognized and interpreted to be a result of vadose diagenesis by Dunham. Modern beachrock from the intertidal zone was noted to have grains that were more fitted to each other than grainstones forming in subtidal settings. Dissolution is interpreted to occur at grain contacts which over time flattens the contact and leads to the grains “fitting” to each other. There may be some pillars of undissolved material that preserve gaps between the grains that are later filled in with isopachous rim cement. The rocks have the appearance of being compacted and indeed this could be called “vadose compaction.” Burial compaction can be ruled out because there are few pressure solution features and the isopachous rim cement clearly postdates the fitting of the grains. Recognition of this important feature can help to identify cryptic exposure surfaces and sequence boundaries that otherwise might be difficult to recognize. Panel_15093 Panel_15093 11:30 AM 11:50 AM

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Layered evaporite sequences (LES) consist of interbedded lithologies of variable strength ranging from weak carnallite and halite to stronger anhydrite, carbonates, siliclastics, and volcanics. The internal deformation depends largely on the mode of salt tectonics. Here, we compare and contrast the internal geometries produced during vertical subsidence of minibasins and associated passive diapirism or during lateral contraction and consequent inflation. In a 2D section, bed lengths increase as material moves from beneath minibasins into diapirs that grow in height, with the extension magnitude partly dependent on diapir width. This results in linked stretching and folding of incompetent layers, boudinage of competent layers into stringers, and rotation of stringers to steeper attitudes that is enhanced by vertically-oriented shear within the diapir. There is also a component of contraction in 3D as material converges from surrounding minibasins into the diapir, creating radial folds and curtain folds. The combination of stringer disruption and rotation results in low seismic coherence and the transparent seismic character typical of passive diapirs. In contrast, lateral shortening of an LES leads to internal contractional folding and consequent inflation of the salt. Because rocks are much stronger under compression than under tension, bedding is more likely to be maintained in more competent stratal packages. Moreover, bending stresses lead to extension and mechanical breakup in anticlines but contraction and bed coherence in synclines. The result on seismic data is a greater tendency to image preserved internal layering than in passive diapirs, with synclines observed more commonly and anticlines more likely to be disrupted and therefore transparent. Examples of both styles can be observed in numerous salt basins, but the best example is that of the Brazilian offshore. Although different areas originally had the same LES with similar internal layering, the seismic character differs greatly. In the proximal Santos Basin and the Campos Basin, for example, passive diapirs are largely transparent. However, over the São Paulo Plateau (distal Santos Basin), internal layering is prominent and characterized by gently to strongly folded strata enhanced by internal density contrasts. This is an area dominated by contraction and inflation, with complex internal deformation, in response to basinward movement of salt in the footwall of the Cabo Frio fault zone. Layered evaporite sequences (LES) consist of interbedded lithologies of variable strength ranging from weak carnallite and halite to stronger anhydrite, carbonates, siliclastics, and volcanics. The internal deformation depends largely on the mode of salt tectonics. Here, we compare and contrast the internal geometries produced during vertical subsidence of minibasins and associated passive diapirism or during lateral contraction and consequent inflation. In a 2D section, bed lengths increase as material moves from beneath minibasins into diapirs that grow in height, with the extension magnitude partly dependent on diapir width. This results in linked stretching and folding of incompetent layers, boudinage of competent layers into stringers, and rotation of stringers to steeper attitudes that is enhanced by vertically-oriented shear within the diapir. There is also a component of contraction in 3D as material converges from surrounding minibasins into the diapir, creating radial folds and curtain folds. The combination of stringer disruption and rotation results in low seismic coherence and the transparent seismic character typical of passive diapirs. In contrast, lateral shortening of an LES leads to internal contractional folding and consequent inflation of the salt. Because rocks are much stronger under compression than under tension, bedding is more likely to be maintained in more competent stratal packages. Moreover, bending stresses lead to extension and mechanical breakup in anticlines but contraction and bed coherence in synclines. The result on seismic data is a greater tendency to image preserved internal layering than in passive diapirs, with synclines observed more commonly and anticlines more likely to be disrupted and therefore transparent. Examples of both styles can be observed in numerous salt basins, but the best example is that of the Brazilian offshore. Although different areas originally had the same LES with similar internal layering, the seismic character differs greatly. In the proximal Santos Basin and the Campos Basin, for example, passive diapirs are largely transparent. However, over the São Paulo Plateau (distal Santos Basin), internal layering is prominent and characterized by gently to strongly folded strata enhanced by internal density contrasts. This is an area dominated by contraction and inflation, with complex internal deformation, in response to basinward movement of salt in the footwall of the Cabo Frio fault zone. Panel_15414 Panel_15414 8:05 AM 8:25 AM

Primary salt welds form at the base of minibasins in response to complete evacuation of autochthonous salt. Analytical and numerical models suggest it is difficult to completely remove salt from a weld by viscous flow alone, which is especially true in multilayered evaporites, within which flow is likely heterogeneous due to lithologically controlled viscosity variations. Welds are of importance in the hydrocarbon industry because they may provide a hydrodynamic seal and trap hydrocarbons or may allow transmission of fluids from source to reservoir rocks. Few papers document the subsurface expression of welds, principally because of they have not been penetrated or because associated data are proprietary. We use 3D seismic and borehole data from the Santos Basin, offshore Brazil to characterise the geological and geophysical expression of a primary weld associated with the flow of Aptian salt. Seismic data suggest that, locally, presalt and postsalt rocks are in contact at the base of an Upper Cretaceous minibasin, implying that several apparent welds, separated by low-relief salt pillows, are present. However, borehole data indicate that 22 m of anhydrite, carbonate and sandstone are present in one of the welds, indicating that this and other welds may be incomplete. Our study shows that seismic data may be unable to discriminate between a complete and incomplete weld, and we suggest that, during the subsurface analysis of welds, the term ‘apparent weld’ is used until borehole data unequivocally proves the absence of salt. Furthermore, we speculate that preferential expulsion of halite and potash salt from the autochthonous layer during viscous flow and welding resulted in the formation of an incomplete weld, which, when compared to the initial autochthonous layer, is volumetrically enriched in non-evaporite lithologies and relatively viscous evaporite lithologies (anhydrite). The composition and stratigraphy of the autochthonous layer may thus dictate weld thickness. Primary salt welds form at the base of minibasins in response to complete evacuation of autochthonous salt. Analytical and numerical models suggest it is difficult to completely remove salt from a weld by viscous flow alone, which is especially true in multilayered evaporites, within which flow is likely heterogeneous due to lithologically controlled viscosity variations. Welds are of importance in the hydrocarbon industry because they may provide a hydrodynamic seal and trap hydrocarbons or may allow transmission of fluids from source to reservoir rocks. Few papers document the subsurface expression of welds, principally because of they have not been penetrated or because associated data are proprietary. We use 3D seismic and borehole data from the Santos Basin, offshore Brazil to characterise the geological and geophysical expression of a primary weld associated with the flow of Aptian salt. Seismic data suggest that, locally, presalt and postsalt rocks are in contact at the base of an Upper Cretaceous minibasin, implying that several apparent welds, separated by low-relief salt pillows, are present. However, borehole data indicate that 22 m of anhydrite, carbonate and sandstone are present in one of the welds, indicating that this and other welds may be incomplete. Our study shows that seismic data may be unable to discriminate between a complete and incomplete weld, and we suggest that, during the subsurface analysis of welds, the term ‘apparent weld’ is used until borehole data unequivocally proves the absence of salt. Furthermore, we speculate that preferential expulsion of halite and potash salt from the autochthonous layer during viscous flow and welding resulted in the formation of an incomplete weld, which, when compared to the initial autochthonous layer, is volumetrically enriched in non-evaporite lithologies and relatively viscous evaporite lithologies (anhydrite). The composition and stratigraphy of the autochthonous layer may thus dictate weld thickness. Panel_15416 Panel_15416 8:25 AM 8:45 AM

The bathymetric datum with respect to global sea-level for Aptian salt deposition in the S. Atlantic is hotly debated. Some models propose that salt was deposited in an isolated ocean basin in which local sea-level was 2-3 km below the global level. In this study we determine the palaeo-bathymetry of base Aptian salt deposition on the Angolan rifted continental margin using 2D reverse post-breakup thermal subsidence modelling. The reverse post-breakup thermal subsidence modelling process consists of sequential flexural isostatic backstripping of the post-breakup sedimentary sequences, decompaction of remaining sedimentary units and reverse modelling of post-breakup lithosphere thermal subsidence. The reverse post-breakup lithosphere thermal subsidence requires 2D knowledge of the rifted continental margin lithosphere beta stretching factor which is determined from gravity inversion. The analysis has been applied to the ION-GXT CS1-2400 deep long-offset seismic reflection profile and the P3 and P7+11 seismic cross-sections of Contrucci et al. (2004) offshore N Angola. Reverse post-breakup subsidence modelling restores the proximal autochthonous base salt to near sea-level at breakup time but not the most distal base salt. In contrast the predicted bathymetries for the base distal salt are much greater ranging between 1.0 and 3.0 km. The predicted bathymetries of the first unequivocal oceanic crust are approximately 2.5 km as expected for newly formed oceanic crust of normal thickness. The preferred interpretation is that all Aptian salt in the Angola margin study areas was deposited at or near global sea-level but that while proximal base salt subsided by thermal subsidence alone, the distal salt experienced both late syn-rift and thermal subsidence. This is consistent with seismic evidence which shows that the base distal salt is extensionally faulted indicating that the crust under the distal salt was being actively thinned during salt deposition, while in contrast the proximal salts were formed in a region where crustal thinning had already taken place and had ceased. An alternative interpretation is that the distal salt moved down-slope during breakup to its present position in much deeper water (and is para-autochthonous). The difference between restored base salt palaeo-bathymetries for proximal and distal salt mitigates against, but does not exclude, a depositional origin in a deep isolated ocean basin. The bathymetric datum with respect to global sea-level for Aptian salt deposition in the S. Atlantic is hotly debated. Some models propose that salt was deposited in an isolated ocean basin in which local sea-level was 2-3 km below the global level. In this study we determine the palaeo-bathymetry of base Aptian salt deposition on the Angolan rifted continental margin using 2D reverse post-breakup thermal subsidence modelling. The reverse post-breakup thermal subsidence modelling process consists of sequential flexural isostatic backstripping of the post-breakup sedimentary sequences, decompaction of remaining sedimentary units and reverse modelling of post-breakup lithosphere thermal subsidence. The reverse post-breakup lithosphere thermal subsidence requires 2D knowledge of the rifted continental margin lithosphere beta stretching factor which is determined from gravity inversion. The analysis has been applied to the ION-GXT CS1-2400 deep long-offset seismic reflection profile and the P3 and P7+11 seismic cross-sections of Contrucci et al. (2004) offshore N Angola. Reverse post-breakup subsidence modelling restores the proximal autochthonous base salt to near sea-level at breakup time but not the most distal base salt. In contrast the predicted bathymetries for the base distal salt are much greater ranging between 1.0 and 3.0 km. The predicted bathymetries of the first unequivocal oceanic crust are approximately 2.5 km as expected for newly formed oceanic crust of normal thickness. The preferred interpretation is that all Aptian salt in the Angola margin study areas was deposited at or near global sea-level but that while proximal base salt subsided by thermal subsidence alone, the distal salt experienced both late syn-rift and thermal subsidence. This is consistent with seismic evidence which shows that the base distal salt is extensionally faulted indicating that the crust under the distal salt was being actively thinned during salt deposition, while in contrast the proximal salts were formed in a region where crustal thinning had already taken place and had ceased. An alternative interpretation is that the distal salt moved down-slope during breakup to its present position in much deeper water (and is para-autochthonous). The difference between restored base salt palaeo-bathymetries for proximal and distal salt mitigates against, but does not exclude, a depositional origin in a deep isolated ocean basin. Panel_15419 Panel_15419 8:45 AM 9:05 AM

Upheaval Dome is an eroded structural dome that exposes Mesozoic strata along with associated folds, faults and sand injectites in the Paradox basin, SE Utah. Multiple interpretations for its origin have been proposed, but the two remaining viable hypotheses are at opposite ends of the geologic spectrum: one proposing long-term salt-related deformation and growth of the structure, the other a catastrophic meteorite impact. Analysis of stratigraphic field data collected in Triassic to Jurassic-aged strata adjacent to Upheaval Dome reveals: (1) stratigraphic thicknesses from measured sections for the Kayenta Formation (~199 to ~195 Ma) that range from 7 meters to 224 meters, and projected thicknesses in cross section that can exceed 400 meters; (2) distinct changes in facies distributions in relation to mapped structures; (3) localized angular unconformities and stratal-onlap surfaces; (4) blocks of Triassic Chinle Formation encased in younger Jurassic Wingate Sandstone adjacent to thinned, Wingate lobes, that apparently downlap onto the underlying Chinle. Structural analysis at Upheaval Dome reveals: (1) synclinal growth axes and associated depositional centers shift away from the center of the dome throughout the Late Triassic/Early Jurassic; (2) stratigraphic thicknesses increase across normal faults on the scale of meters to tens of meters; (3) thrust faults within the Kayenta Formation verge to the southeast regardless of location around the structure. These structural features and associated growth strata offer compelling evidence for long-term deformation compatible with salt tectonics at Upheaval Dome during the Late Triassic/Early Jurassic. Sparse indicators of catastrophic impact are present in the Kayenta Formation in the form of two shocked quartz grains, orders of magnitude less than would be expected <1 km from a meteorite impact site. We interpret these grains to be detrital and sourced from outside the Paradox basin. In our interpretation of salt-related deformation, we discuss the merits and drawbacks of a model invoking collapse over a buried salt high to a prior model of a pinched-off diapiric feeder to an eroded salt glacier. The possibility that a meteorite impact of Late Permian to Early Triassic age initiated the growth of an isolated salt pillow in the western part of the northern Paradox Basin requires further investigation. Upheaval Dome is an eroded structural dome that exposes Mesozoic strata along with associated folds, faults and sand injectites in the Paradox basin, SE Utah. Multiple interpretations for its origin have been proposed, but the two remaining viable hypotheses are at opposite ends of the geologic spectrum: one proposing long-term salt-related deformation and growth of the structure, the other a catastrophic meteorite impact. Analysis of stratigraphic field data collected in Triassic to Jurassic-aged strata adjacent to Upheaval Dome reveals: (1) stratigraphic thicknesses from measured sections for the Kayenta Formation (~199 to ~195 Ma) that range from 7 meters to 224 meters, and projected thicknesses in cross section that can exceed 400 meters; (2) distinct changes in facies distributions in relation to mapped structures; (3) localized angular unconformities and stratal-onlap surfaces; (4) blocks of Triassic Chinle Formation encased in younger Jurassic Wingate Sandstone adjacent to thinned, Wingate lobes, that apparently downlap onto the underlying Chinle. Structural analysis at Upheaval Dome reveals: (1) synclinal growth axes and associated depositional centers shift away from the center of the dome throughout the Late Triassic/Early Jurassic; (2) stratigraphic thicknesses increase across normal faults on the scale of meters to tens of meters; (3) thrust faults within the Kayenta Formation verge to the southeast regardless of location around the structure. These structural features and associated growth strata offer compelling evidence for long-term deformation compatible with salt tectonics at Upheaval Dome during the Late Triassic/Early Jurassic. Sparse indicators of catastrophic impact are present in the Kayenta Formation in the form of two shocked quartz grains, orders of magnitude less than would be expected <1 km from a meteorite impact site. We interpret these grains to be detrital and sourced from outside the Paradox basin. In our interpretation of salt-related deformation, we discuss the merits and drawbacks of a model invoking collapse over a buried salt high to a prior model of a pinched-off diapiric feeder to an eroded salt glacier. The possibility that a meteorite impact of Late Permian to Early Triassic age initiated the growth of an isolated salt pillow in the western part of the northern Paradox Basin requires further investigation. Panel_15413 Panel_15413 9:05 AM 9:25 AM

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Many salt diapirs are known to be initiated by, and widen during, regional extension. However, field exposures of strata flanking the southeast portion of the NW-SE trending Gypsum Valley salt wall (Paradox Basin, Colorado), combined with subsurface data, demonstrate that passive diapirs can also widen in the absence of extension. At a regional scale, the diapir is flanked by minibasins with depocenters that shift toward the diapir over time. At a more local scale, Jurassic Morrison Fm. and younger units form an anticline over the northeastern edge of the diapir; deeper strata are rarely exposed, but seismic and well data show minor (max ~25 degrees) dip away from the diapir and relatively subtle thickness changes. In contrast, the southwestern side is dominated by a panel of near-vertical Pennsylvanian Honaker Trail Fm. and uppermost Paradox Fm. black shales adjacent to Paradox Fm. gypsum. The panel is overlain by a wedge of thinning Permian Cutler Group and Triassic and Jurassic strata, all capped by a gently dipping mid-Jurassic unconformity, with increasing angular truncation toward the diapir and Jurassic Entrada and younger strata just above. The vertical panel is interpreted as a megaflap, with seismic and well data showing that it extends ~2.6 km up the side of the diapir over a lateral distance of ~5 km and thins from 350 m in its basinal position to 200 m beneath the unconformity. There is negligible bed-lengthening in the exposed upper part of the megaflap, which is consistent with its length being close to the 3 km width of the diapir at this location. Moreover, conglomerates within the Honaker Trail Fm. in the megaflap contain clasts of Paradox Fm. units, demonstrating the presence of a exposed diapir shortly after evaporite deposition. The observations are combined with cross-section restoration to illustrate the evolution of the diapir. It was initiated as a narrow diapir during Honaker Trail time at the northeastern edge of an inflated pillow, now the northeastern edge of the salt wall. Whereas the northeastern flank subsided vertically with only minor upturn near the diapir, the relative subsidence of the southwestern flank was accompanied by the roof of the inflated salt rolling through a monoclinal hinge from subhorizontal to near-vertical attitudes, thereby forming the megaflap. As the roof rolled over the edge of the diapir, the diapir progressively widened without any regional extension. Many salt diapirs are known to be initiated by, and widen during, regional extension. However, field exposures of strata flanking the southeast portion of the NW-SE trending Gypsum Valley salt wall (Paradox Basin, Colorado), combined with subsurface data, demonstrate that passive diapirs can also widen in the absence of extension. At a regional scale, the diapir is flanked by minibasins with depocenters that shift toward the diapir over time. At a more local scale, Jurassic Morrison Fm. and younger units form an anticline over the northeastern edge of the diapir; deeper strata are rarely exposed, but seismic and well data show minor (max ~25 degrees) dip away from the diapir and relatively subtle thickness changes. In contrast, the southwestern side is dominated by a panel of near-vertical Pennsylvanian Honaker Trail Fm. and uppermost Paradox Fm. black shales adjacent to Paradox Fm. gypsum. The panel is overlain by a wedge of thinning Permian Cutler Group and Triassic and Jurassic strata, all capped by a gently dipping mid-Jurassic unconformity, with increasing angular truncation toward the diapir and Jurassic Entrada and younger strata just above. The vertical panel is interpreted as a megaflap, with seismic and well data showing that it extends ~2.6 km up the side of the diapir over a lateral distance of ~5 km and thins from 350 m in its basinal position to 200 m beneath the unconformity. There is negligible bed-lengthening in the exposed upper part of the megaflap, which is consistent with its length being close to the 3 km width of the diapir at this location. Moreover, conglomerates within the Honaker Trail Fm. in the megaflap contain clasts of Paradox Fm. units, demonstrating the presence of a exposed diapir shortly after evaporite deposition. The observations are combined with cross-section restoration to illustrate the evolution of the diapir. It was initiated as a narrow diapir during Honaker Trail time at the northeastern edge of an inflated pillow, now the northeastern edge of the salt wall. Whereas the northeastern flank subsided vertically with only minor upturn near the diapir, the relative subsidence of the southwestern flank was accompanied by the roof of the inflated salt rolling through a monoclinal hinge from subhorizontal to near-vertical attitudes, thereby forming the megaflap. As the roof rolled over the edge of the diapir, the diapir progressively widened without any regional extension. Panel_15421 Panel_15421 10:10 AM 10:30 AM

Megaflaps are panels of near-vertical to overturned deep minibasin strata that extend far up the flanks of primary and secondary diapirs. Vertical relief on megaflaps is on the order of a few kilometers and internally the strata are typically slightly convergent to subparallel. Megaflaps are increasingly being identified post-drill in salt basins worldwide (e.g. Gulf of Mexico, Brazil, Angola), but usually to the detriment of prospectivity when wells encounter unexpectedly old and steep strata due to poor seismic imaging at the salt-sediment interface. In order to increase pre-drill predictability, outcrop-based investigations of megaflap geometric styles, stratal geometries, depositional facies and stratigraphy, and small-scale deformation are imperative for the characterization of salt-flank trap potential. In the Willouran Ranges, South Australia, outcrop exposures provide an oblique cross-sectional view of a megaflap comprising Neoproterozoic Witchelina Quartzite adjacent to the Witchelina diapir. We use stratigraphic and structural relationships of the Witchelina megaflap to test and refine the existing models of megaflap formation. The Witchelina megaflap has vertical relief of ~2.5km. The lower boundary is a low-angle erosional onlap surface on to a broad salt pillow, while the upper boundary is a diffuse zone with progressive stratal rotation and thinning. Internally, strata are highly convergent and thinned. The near-vertical diapir-flanking strata thin upward from 1450 m at the base to 60 m at the upper reaches. The Witchelina Quartzite was deposited in a high-energy shoreface environment during continental rifting. Depositional thinning over an initially broad salt pillow was punctuated by transgressive erosional events that stripped the crestal cover over the salt pillow. Five stratigraphic intervals are informally defined for the Witchelina Quartzite (Now). Progressively younger stratigraphic intervals (Now 1-4) thin and onlap higher up the inflating diapir flank as it transitioned from a pillow to a steeper-sided diapir. The youngest interval (Now 5), which records minibasin fill adjacent to true diapiric rise, is not included in the megaflap panel. Small-scale deformation reflects minor bed lengthening, as only 2-3% structural thinning was documented near the top of the megaflap. Subsequent shortening during the Delamerian Orogeny enhanced the upturn of the Witchelina megaflap. Megaflaps are panels of near-vertical to overturned deep minibasin strata that extend far up the flanks of primary and secondary diapirs. Vertical relief on megaflaps is on the order of a few kilometers and internally the strata are typically slightly convergent to subparallel. Megaflaps are increasingly being identified post-drill in salt basins worldwide (e.g. Gulf of Mexico, Brazil, Angola), but usually to the detriment of prospectivity when wells encounter unexpectedly old and steep strata due to poor seismic imaging at the salt-sediment interface. In order to increase pre-drill predictability, outcrop-based investigations of megaflap geometric styles, stratal geometries, depositional facies and stratigraphy, and small-scale deformation are imperative for the characterization of salt-flank trap potential. In the Willouran Ranges, South Australia, outcrop exposures provide an oblique cross-sectional view of a megaflap comprising Neoproterozoic Witchelina Quartzite adjacent to the Witchelina diapir. We use stratigraphic and structural relationships of the Witchelina megaflap to test and refine the existing models of megaflap formation. The Witchelina megaflap has vertical relief of ~2.5km. The lower boundary is a low-angle erosional onlap surface on to a broad salt pillow, while the upper boundary is a diffuse zone with progressive stratal rotation and thinning. Internally, strata are highly convergent and thinned. The near-vertical diapir-flanking strata thin upward from 1450 m at the base to 60 m at the upper reaches. The Witchelina Quartzite was deposited in a high-energy shoreface environment during continental rifting. Depositional thinning over an initially broad salt pillow was punctuated by transgressive erosional events that stripped the crestal cover over the salt pillow. Five stratigraphic intervals are informally defined for the Witchelina Quartzite (Now). Progressively younger stratigraphic intervals (Now 1-4) thin and onlap higher up the inflating diapir flank as it transitioned from a pillow to a steeper-sided diapir. The youngest interval (Now 5), which records minibasin fill adjacent to true diapiric rise, is not included in the megaflap panel. Small-scale deformation reflects minor bed lengthening, as only 2-3% structural thinning was documented near the top of the megaflap. Subsequent shortening during the Delamerian Orogeny enhanced the upturn of the Witchelina megaflap. Panel_15417 Panel_15417 10:30 AM 10:50 AM

Geological surface data, exploration well log data and seismic 2D data indicate that large volumes of evaporites, mostly salt, but also gypsum and anhydrite, were emplaced during passive-margin development of the Tethys in southern Iberia, today part of the Guadalquivir Allochthon of the Central and Western Betic Cordillera (Southern Spain). Syn-tectonic sediments, remnants of mini-basins, and re-deposited evaporites within deep-water strata suggest that the main emplacement of the salt canopies took place during Upper Cretaceous and Paleocene time. This age results much older than the Miocene to Pliocene emplacement of the Guadalquivir Allochthon. Mostly allochthonous salt bodies occupying the higher and often frontal structural thrust sheet of the Betic Cordillera compose this unit. Late Neogene (Upper Miocene to Pliocene) Alpine compression within the Betic fold-and-thrust belt strongly deformed the allochthonous salt system. During this event, the Guadalquivir Allochthon formed a thrust sheet that was emplaced above the Jurassic-Cretaceous inverted, passive margin (formed by the Pre and Sub-Betic Nappes). The Triassic section of the Guadalquivir Allochthon (>2 km thick salt unit) strongly differs from the underlying sub-autochthonous Triassic section of the Sub-and Pre-Betic units, which is formed by limestone and evaporite strata indicative of pre, syn- and post-rift sabkha type sedimentation. Passive-margin Triassic salt structures can also be found in the antithetic North African margin along the Rif and Tell belts, in Morocco, Algeria and Tunisia. Compared to the Betic Cordillera in Spain, this margin had a less-matured allochthonous canopy system with an older age of emplacement, because it probably occurred during the early Upper Cretaceous. Geological surface data, exploration well log data and seismic 2D data indicate that large volumes of evaporites, mostly salt, but also gypsum and anhydrite, were emplaced during passive-margin development of the Tethys in southern Iberia, today part of the Guadalquivir Allochthon of the Central and Western Betic Cordillera (Southern Spain). Syn-tectonic sediments, remnants of mini-basins, and re-deposited evaporites within deep-water strata suggest that the main emplacement of the salt canopies took place during Upper Cretaceous and Paleocene time. This age results much older than the Miocene to Pliocene emplacement of the Guadalquivir Allochthon. Mostly allochthonous salt bodies occupying the higher and often frontal structural thrust sheet of the Betic Cordillera compose this unit. Late Neogene (Upper Miocene to Pliocene) Alpine compression within the Betic fold-and-thrust belt strongly deformed the allochthonous salt system. During this event, the Guadalquivir Allochthon formed a thrust sheet that was emplaced above the Jurassic-Cretaceous inverted, passive margin (formed by the Pre and Sub-Betic Nappes). The Triassic section of the Guadalquivir Allochthon (>2 km thick salt unit) strongly differs from the underlying sub-autochthonous Triassic section of the Sub-and Pre-Betic units, which is formed by limestone and evaporite strata indicative of pre, syn- and post-rift sabkha type sedimentation. Passive-margin Triassic salt structures can also be found in the antithetic North African margin along the Rif and Tell belts, in Morocco, Algeria and Tunisia. Compared to the Betic Cordillera in Spain, this margin had a less-matured allochthonous canopy system with an older age of emplacement, because it probably occurred during the early Upper Cretaceous. Panel_15420 Panel_15420 10:50 AM 11:10 AM

The Isthmian Saline Sub-basin in the Southeastern Gulf of Mexico is part of a foreland basin complex. These pre-existing salt structures exert a strong control on the regional tectonic styles and kinematics of the fold belts in the Chiapas and Campeche areas. Parts of the salt basin are already incorporated in the Chiapas fold belt and adjoining fold belts. The Isthmian Saline Sub-basin and the front of Sierra de Chiapas Range provinces represent a major exploration challenge due to their structural complexity, which is partly controlled by the distribution of Jurassic salt sediments and present-day salt structures. The salt distribution, the evolution of the diapirs and minibasins since the Jurassic and their impact on the regional tectonic evolution of the deformation front of the fold belts are still poorly understood. Regional tectonic analysis based on 3D seismic reflection data, well data and geological maps provided by PEMEX give insights in the tectono-stratigraphic evolution of the salt basin and adjacent mountain front. The N-S trending, E-vergent “Cerro Pelon” anticline, which is located just North of the modern deformation front allows to study the salt basin extend and controls of pre-salt basement structures on salt deposition and regional tectonic evolution. In the Oligocene and Miocene foreland basin, the fold core exposes Middle Jurassic sediments (Todos Santos Formation) time-equivalent to the salt sediments and Eagle Milles Formation of the Northern Gulf of Mexico. Towards the northern portion of the anticline some of the exploration wells reported the presence of diapir salt, whereas none of the wells south of the anticline have encountered salt. Preliminary seismic interpretation results show that the onshore salt basin is characterized by spectacular salt structures including 10 km tall salt diapirs and minibasins with up to 6 km thick Paleogene-Miocene sediments sourced from the near by mountain ranges. Early salt anticlines, salt walls and pillows formed during early Cretaceous times. Contractional deformation in Paleocene to Miocene times caused by the lateral movement of the Chortís block transformed the salt anticlines into tall contractional diapirs and salt tongues and created large intervening depocenter with up to 6 km thick sediment fill. The Isthmian Saline Sub-basin in the Southeastern Gulf of Mexico is part of a foreland basin complex. These pre-existing salt structures exert a strong control on the regional tectonic styles and kinematics of the fold belts in the Chiapas and Campeche areas. Parts of the salt basin are already incorporated in the Chiapas fold belt and adjoining fold belts. The Isthmian Saline Sub-basin and the front of Sierra de Chiapas Range provinces represent a major exploration challenge due to their structural complexity, which is partly controlled by the distribution of Jurassic salt sediments and present-day salt structures. The salt distribution, the evolution of the diapirs and minibasins since the Jurassic and their impact on the regional tectonic evolution of the deformation front of the fold belts are still poorly understood. Regional tectonic analysis based on 3D seismic reflection data, well data and geological maps provided by PEMEX give insights in the tectono-stratigraphic evolution of the salt basin and adjacent mountain front. The N-S trending, E-vergent “Cerro Pelon” anticline, which is located just North of the modern deformation front allows to study the salt basin extend and controls of pre-salt basement structures on salt deposition and regional tectonic evolution. In the Oligocene and Miocene foreland basin, the fold core exposes Middle Jurassic sediments (Todos Santos Formation) time-equivalent to the salt sediments and Eagle Milles Formation of the Northern Gulf of Mexico. Towards the northern portion of the anticline some of the exploration wells reported the presence of diapir salt, whereas none of the wells south of the anticline have encountered salt. Preliminary seismic interpretation results show that the onshore salt basin is characterized by spectacular salt structures including 10 km tall salt diapirs and minibasins with up to 6 km thick Paleogene-Miocene sediments sourced from the near by mountain ranges. Early salt anticlines, salt walls and pillows formed during early Cretaceous times. Contractional deformation in Paleocene to Miocene times caused by the lateral movement of the Chortís block transformed the salt anticlines into tall contractional diapirs and salt tongues and created large intervening depocenter with up to 6 km thick sediment fill. Panel_15418 Panel_15418 11:10 AM 11:30 AM

The Needles District of Canyonlands, Utah contains coupled extensional faults, salt diapirs and a sinuous anticline that all grow in response to gravitational stresses driven by erosion along the Colorado River and its tributaries. Interferometric Synthetic Aperture Radar (InSAR) and 3D numerical modeling are used to map strain in the region and define how it relates to salt structures and patterns of surface deformation. InSAR results from ERS satellite scenes taken between 1992 and 2000 show line-of-sight (LOS) deformation rates of ~1-3 mm/yr both in the grabens and further south, where extension is accommodated by the Imperial Valley fault. These rates are similar to that measured by a creepmeter installed across the Imperial Valley. Analysis of Envisat InSAR data from 2006-2010 shows higher LOS displacement rates in the grabens of up to 5 mm/yr and LOS rates of ~1-3 mm/yr in the area to the southwest. Envisat data could thus be marking an increase in displacement rates over time. However, these results contain uncertainty because they indicate higher rates of subsidence in tributaries of the Colorado River Canyon, where uplift should dominate. 3D numerical models produced using FLAC3D are used to test how plastic flow of evaporites and brittle extension of overburden are coupled during deformation. Topographic models of the region were made using a 50 m resolution digital elevation dataset. Topography was overlaid onto a strain softening, mohr coulomb rheology to represent the 400 m thick sequence of strata that overlie the salt. A viscous, flat lying salt layer with a thickness of 340 m comprised the model beneath the overburden. The models were run for 2,000 years to test how topography currently drives deformation. Results show the sensitivity of strain to topography in the region. In particular, displacement is focused to the northwest, directly toward the river canyon in the grabens region. However, in the area around the Imperial Valley fault, the geometry of the river canyon appears to direct strain to both the north and west, which may be related to the change in strike in faults in this area. Additionally, salt deformation in the models show overburden gliding as the dominant deformation mechanism, not salt flow, consistent with previous studies. Comparison between the strain rate of the models and InSAR suggests they are similar, further demonstrating that overburden gliding can accommodate the observed strain. The Needles District of Canyonlands, Utah contains coupled extensional faults, salt diapirs and a sinuous anticline that all grow in response to gravitational stresses driven by erosion along the Colorado River and its tributaries. Interferometric Synthetic Aperture Radar (InSAR) and 3D numerical modeling are used to map strain in the region and define how it relates to salt structures and patterns of surface deformation. InSAR results from ERS satellite scenes taken between 1992 and 2000 show line-of-sight (LOS) deformation rates of ~1-3 mm/yr both in the grabens and further south, where extension is accommodated by the Imperial Valley fault. These rates are similar to that measured by a creepmeter installed across the Imperial Valley. Analysis of Envisat InSAR data from 2006-2010 shows higher LOS displacement rates in the grabens of up to 5 mm/yr and LOS rates of ~1-3 mm/yr in the area to the southwest. Envisat data could thus be marking an increase in displacement rates over time. However, these results contain uncertainty because they indicate higher rates of subsidence in tributaries of the Colorado River Canyon, where uplift should dominate. 3D numerical models produced using FLAC3D are used to test how plastic flow of evaporites and brittle extension of overburden are coupled during deformation. Topographic models of the region were made using a 50 m resolution digital elevation dataset. Topography was overlaid onto a strain softening, mohr coulomb rheology to represent the 400 m thick sequence of strata that overlie the salt. A viscous, flat lying salt layer with a thickness of 340 m comprised the model beneath the overburden. The models were run for 2,000 years to test how topography currently drives deformation. Results show the sensitivity of strain to topography in the region. In particular, displacement is focused to the northwest, directly toward the river canyon in the grabens region. However, in the area around the Imperial Valley fault, the geometry of the river canyon appears to direct strain to both the north and west, which may be related to the change in strike in faults in this area. Additionally, salt deformation in the models show overburden gliding as the dominant deformation mechanism, not salt flow, consistent with previous studies. Comparison between the strain rate of the models and InSAR suggests they are similar, further demonstrating that overburden gliding can accommodate the observed strain. Panel_15415 Panel_15415 11:30 AM 11:50 AM

Panel_14482 Panel_14482 8:00 AM 11:50 AM

Panel_15763 Panel_15763 8:00 AM 12:00 AM

The U.S. Energy Independence and Security Act of 2007 authorized the U.S. Geological Survey (USGS) to prepare a national assessment of the potential volume of hydrocarbons recoverable by injection of carbon dioxide (CO2) in known oil reservoirs. The implementation of CO2 enhanced oil recovery (CO2-EOR) techniques can increase the U.S. recoverable oil resource base and reduce CO2 released to the atmosphere by storing the residual CO2 in reservoir pore space vacated by produced oil. The USGS has developed an assessment methodology for estimating potential incremental technically recoverable oil resources that may be producible by implementing CO2-EOR in reservoirs with appropriate depth, pressure, and oil composition for CO2 injection. The methodology relies on a reservoir-level database that incorporates commercially available geologic and engineering data; play averages or province averages of reservoir data are used to populate incomplete records. This allows computation of an initial estimate of original oil in place (OOIP) for each reservoir. For each assessed play, USGS geologists evaluate probability distributions associated with estimates of average porosity and initial oil saturation for the largest reservoirs, and are responsible for evaluating EOR failure risk. Simulation is used to produce a probability distribution for the OOIP that has as its mean the database OOIP estimate. The resulting distribution is scaled and applied to the database point estimates of other EOR reservoir candidates in the play. Distributions of recovery factors are prepared based on EOR method (miscible or immiscible) and reservoir lithology. The distribution of incremental oil is computed by multiplying the appropriate probability distribution of recovery factors by the candidate reservoir distribution of OOIP. An estimate of the CO2 remaining in the reservoir after the CO2-EOR process is completed also is included in the methodology. Assessment results will be aggregated to the play, basin, region, and national levels. This assessment methodology has been tested and produced realistic results for the Permian Basin Horseshoe Atoll play comprising 84 reservoirs. Once the assessment methodology has been thoroughly reviewed by a panel of industry, academic, and other experts, the USGS plans to conduct a national assessment of incremental oil technically recoverable using the CO2-EOR process. The U.S. Energy Independence and Security Act of 2007 authorized the U.S. Geological Survey (USGS) to prepare a national assessment of the potential volume of hydrocarbons recoverable by injection of carbon dioxide (CO₂) in known oil reservoirs. The implementation of CO₂ enhanced oil recovery (CO₂-EOR) techniques can increase the U.S. recoverable oil resource base and reduce CO₂ released to the atmosphere by storing the residual CO₂ in reservoir pore space vacated by produced oil. The USGS has developed an assessment methodology for estimating potential incremental technically recoverable oil resources that may be producible by implementing CO₂-EOR in reservoirs with appropriate depth, pressure, and oil composition for CO₂ injection. The methodology relies on a reservoir-level database that incorporates commercially available geologic and engineering data; play averages or province averages of reservoir data are used to populate incomplete records. This allows computation of an initial estimate of original oil in place (OOIP) for each reservoir. For each assessed play, USGS geologists evaluate probability distributions associated with estimates of average porosity and initial oil saturation for the largest reservoirs, and are responsible for evaluating EOR failure risk. Simulation is used to produce a probability distribution for the OOIP that has as its mean the database OOIP estimate. The resulting distribution is scaled and applied to the database point estimates of other EOR reservoir candidates in the play. Distributions of recovery factors are prepared based on EOR method (miscible or immiscible) and reservoir lithology. The distribution of incremental oil is computed by multiplying the appropriate probability distribution of recovery factors by the candidate reservoir distribution of OOIP. An estimate of the CO₂ remaining in the reservoir after the CO₂-EOR process is completed also is included in the methodology. Assessment results will be aggregated to the play, basin, region, and national levels. This assessment methodology has been tested and produced realistic results for the Permian Basin Horseshoe Atoll play comprising 84 reservoirs. Once the assessment methodology has been thoroughly reviewed by a panel of industry, academic, and other experts, the USGS plans to conduct a national assessment of incremental oil technically recoverable using the CO₂-EOR process. Panel_15470 Panel_15470 8:05 AM 8:25 AM

The Arbuckle Group (Cambro-Ordovician) consists dominantly of shallow shelf carbonates overprinted by karstic features developed during repeated subaerial exposure. The Arbuckle saline aquifer in south-western and south-central Kansas is an ideal candidate for CO2 sequestration because of thickness (600–1000 ft), supercritical depth (>3500 ft), stratigraphic isolation from freshwater aquifers, and limited oil and gas production. In addition, this formation has an extensive history of waste and back flow water disposal in Kansas and Oklahoma. Moreover, the Arbuckle formation is noticeably underpressured which potentially allows for higher volumes of disposal fluids to be accepted without risk of overpressuring of the reservoir. Previously published estimates of CO2 sequestration capacity in the Arbuckle Group in Kansas vary between 1.1 to 8.8 billion metric tons based on static CO2 solubility in brine under in situ pressure and temperature. This work provides a more detailed and comprehensive approach to regional CO2 storage capacity estimations. A detailed geological characterization was performed where existing well log and core data was analyzed and new exploratory wells were drilled in central and western Kansas with extensive logging and coring programs. Based on this analysis, ten potential commercial-scale CO2 injection sites were selected, characterized, and modeled. Accurate calculation of CO2 storage capacity for south-central and south-western Kansas was performed where researchers used several different approaches including volumetric calculations (proposed by Department of Energy and Carbon Sequestration Leadership Form Task Force of CO2 Storage Capacity Estimation), extrapolation based on CO2 storage capacity of selected ten modeled sites, detailed regional model numerical simulation, and using statistical approach. Modeling scenarios included maximum allowable pressure, which was estimated based on calculated fracture pressure gradient, various pressure maintenance scenarios, and boundary conditions. Depending on the proposed scenarios and assumptions for system conditions, estimates for CO2 storage capacity for south-central and south-western Kansas vary between 0.66 to 2 billion metric tons. The Arbuckle Group (Cambro-Ordovician) consists dominantly of shallow shelf carbonates overprinted by karstic features developed during repeated subaerial exposure. The Arbuckle saline aquifer in south-western and south-central Kansas is an ideal candidate for CO₂ sequestration because of thickness (600–1000 ft), supercritical depth (>3500 ft), stratigraphic isolation from freshwater aquifers, and limited oil and gas production. In addition, this formation has an extensive history of waste and back flow water disposal in Kansas and Oklahoma. Moreover, the Arbuckle formation is noticeably underpressured which potentially allows for higher volumes of disposal fluids to be accepted without risk of overpressuring of the reservoir. Previously published estimates of CO₂ sequestration capacity in the Arbuckle Group in Kansas vary between 1.1 to 8.8 billion metric tons based on static CO₂ solubility in brine under in situ pressure and temperature. This work provides a more detailed and comprehensive approach to regional CO₂ storage capacity estimations. A detailed geological characterization was performed where existing well log and core data was analyzed and new exploratory wells were drilled in central and western Kansas with extensive logging and coring programs. Based on this analysis, ten potential commercial-scale CO₂ injection sites were selected, characterized, and modeled. Accurate calculation of CO₂ storage capacity for south-central and south-western Kansas was performed where researchers used several different approaches including volumetric calculations (proposed by Department of Energy and Carbon Sequestration Leadership Form Task Force of CO₂ Storage Capacity Estimation), extrapolation based on CO₂ storage capacity of selected ten modeled sites, detailed regional model numerical simulation, and using statistical approach. Modeling scenarios included maximum allowable pressure, which was estimated based on calculated fracture pressure gradient, various pressure maintenance scenarios, and boundary conditions. Depending on the proposed scenarios and assumptions for system conditions, estimates for CO₂ storage capacity for south-central and south-western Kansas vary between 0.66 to 2 billion metric tons. Panel_15468 Panel_15468 8:25 AM 8:45 AM

Enhanced Oil Recovery (EOR) through immiscible, or multi-contact miscible, gas injection can be unstable to viscous flow instabilities when the mobility ratio between injected gas and displaced oil-in-place is high. Additionally, there is a risk of gravitational flow instabilities associated with, for instance, CO2 injection. Gravitational fingering can occur both when a denser fluid is injected on top of a lighter fluid (e.g. supercritical CO2 may have a higher density than oil in some reservoirs), and also when multiphase compositional effects result in local density variations that may trigger instabilities (i.e. due to evaporation and dissolution of species). In the context of EOR, both viscous and gravitational fingering are detrimental to hydrocarbon recovery, because the instabilities can result in early breakthrough of injection fluids. Carbon sequestration in the top of saline aquifers can also be affected by gravitational fingering when CO2 dissolution locally increases the aqueous phase density. In this scenario the flow instability is beneficial. The gravito-convective mixing of CO2 throughout the aquifer is more efficient than Fickian diffusion alone. A reliable model for viscous and gravitational flow instabilities is critical for EOR and carbon sequestration studies, as well as for various other flow problems. The early onset of fingering instabilities has been investigated analytically by perturbation theory, and the non-linear regime has been considered in numerous simulation studies. However, these studies have generally relied on a range of simplifying assumptions on dimensionality, compositional and phase behavior effects, and boundary conditions. Additionally, simulation results may be model dependent. Particularly, the small-scale onset of fingering is often delayed or suppressed altogether by numerical dispersion when lowest-order methods are used. In this work, we present a unified study of both viscous and gravitational fingering for fully compositional, three-dimensional, multiphase flow, modeled with advanced higher-order finite element methods. Moreover, we compare our simulations on structured and unstructured grids to results from other academic and commercial reservoir simulators. We demonstrate that higher-order methods are essential in predicting fingering behavior, and its potentially disastrous impacts on hydrocarbon recovery, on feasible grid sizes. Enhanced Oil Recovery (EOR) through immiscible, or multi-contact miscible, gas injection can be unstable to viscous flow instabilities when the mobility ratio between injected gas and displaced oil-in-place is high. Additionally, there is a risk of gravitational flow instabilities associated with, for instance, CO₂ injection. Gravitational fingering can occur both when a denser fluid is injected on top of a lighter fluid (e.g. supercritical CO₂ may have a higher density than oil in some reservoirs), and also when multiphase compositional effects result in local density variations that may trigger instabilities (i.e. due to evaporation and dissolution of species). In the context of EOR, both viscous and gravitational fingering are detrimental to hydrocarbon recovery, because the instabilities can result in early breakthrough of injection fluids. Carbon sequestration in the top of saline aquifers can also be affected by gravitational fingering when CO₂ dissolution locally increases the aqueous phase density. In this scenario the flow instability is beneficial. The gravito-convective mixing of CO₂ throughout the aquifer is more efficient than Fickian diffusion alone. A reliable model for viscous and gravitational flow instabilities is critical for EOR and carbon sequestration studies, as well as for various other flow problems. The early onset of fingering instabilities has been investigated analytically by perturbation theory, and the non-linear regime has been considered in numerous simulation studies. However, these studies have generally relied on a range of simplifying assumptions on dimensionality, compositional and phase behavior effects, and boundary conditions. Additionally, simulation results may be model dependent. Particularly, the small-scale onset of fingering is often delayed or suppressed altogether by numerical dispersion when lowest-order methods are used. In this work, we present a unified study of both viscous and gravitational fingering for fully compositional, three-dimensional, multiphase flow, modeled with advanced higher-order finite element methods. Moreover, we compare our simulations on structured and unstructured grids to results from other academic and commercial reservoir simulators. We demonstrate that higher-order methods are essential in predicting fingering behavior, and its potentially disastrous impacts on hydrocarbon recovery, on feasible grid sizes. Panel_15475 Panel_15475 8:45 AM 9:05 AM

The once prolific hydrocarbon reservoirs of the Pennsylvanian Morrowan sequence of northwest Texas through Southeast Colorado in the United States currently presents an opportunity for Carbon Dioxide (CO2) enhanced oil recovery (EOR) and carbon sequestration. The Farnsworth Unit (FWU) of Ochiltree County, Texas operated by Chaparral Energy L.L.C. is the site of a CO2-EOR project using anthropogenic CO2 and a Southwest Regional Partnership on Carbon Sequestration carbon capture, utilization and sequestration project sponsored by the Department of Energy’s National Energy Technology Laboratory. The target reservoir is the upper Morrow sandstone (Morrow-B). Cores and associated thin sections were analyzed to interpret mineralogy, provenance, diagentic history, depositional environment and porosity types. This information, combined with legacy well log data and a new 3D seismic survey, was used to create a fine scale lithofacies based geologic model of the field. Forty-eight wells with permeability and porosity core data were then used for property modeling. In addition, 7 wireline logs were interpreted for porosity and incorporated into the modeling. A variety of geostatistical techniques were used to populate reservoir rock properties. Quality checks were performed to ascertain which geostatistical technique resulted in the best property distribution. The geological model was upscaled for numerical flow simulation. A history match of the waterflood was constructed as the basis for the CO2-EOR study. The performance of the current CO2-flood patterns was analyzed and optimized for CO2 storage and EOR. The lithofacies based geologic model was successfully used to constrain the porosity and permeability distributions. The quality check procedure ensured the well log and core data were honored in the property modeling. The results from the simulation show a great potential for CO2 storage and prolific oil production from the FWU. This study can serve as a benchmark for potential CO2-EOR projects in the Anadarko basin. The once prolific hydrocarbon reservoirs of the Pennsylvanian Morrowan sequence of northwest Texas through Southeast Colorado in the United States currently presents an opportunity for Carbon Dioxide (CO₂) enhanced oil recovery (EOR) and carbon sequestration. The Farnsworth Unit (FWU) of Ochiltree County, Texas operated by Chaparral Energy L.L.C. is the site of a CO₂-EOR project using anthropogenic CO₂ and a Southwest Regional Partnership on Carbon Sequestration carbon capture, utilization and sequestration project sponsored by the Department of Energy’s National Energy Technology Laboratory. The target reservoir is the upper Morrow sandstone (Morrow-B). Cores and associated thin sections were analyzed to interpret mineralogy, provenance, diagentic history, depositional environment and porosity types. This information, combined with legacy well log data and a new 3D seismic survey, was used to create a fine scale lithofacies based geologic model of the field. Forty-eight wells with permeability and porosity core data were then used for property modeling. In addition, 7 wireline logs were interpreted for porosity and incorporated into the modeling. A variety of geostatistical techniques were used to populate reservoir rock properties. Quality checks were performed to ascertain which geostatistical technique resulted in the best property distribution. The geological model was upscaled for numerical flow simulation. A history match of the waterflood was constructed as the basis for the CO₂-EOR study. The performance of the current CO₂-flood patterns was analyzed and optimized for CO₂ storage and EOR. The lithofacies based geologic model was successfully used to constrain the porosity and permeability distributions. The quality check procedure ensured the well log and core data were honored in the property modeling. The results from the simulation show a great potential for CO₂ storage and prolific oil production from the FWU. This study can serve as a benchmark for potential CO₂-EOR projects in the Anadarko basin. Panel_15472 Panel_15472 9:05 AM 9:25 AM

Panel_15764 Panel_15764 9:25 AM 12:00 AM

The Kimmeridgian-Tithonian Dupuy Formation forms the reservoir for the Gorgon CO2 injection project. The injection project will be one of the largest in the world, reducing greenhouse gas emissions from the Gorgon Project by approximately 40 percent. The Project plans to inject between 3.4 and 4.0 million tonnes of reservoir carbon dioxide each year. The project involves CO2 injection, water production to manage reservoir pressure, water disposal into the overlying Barrow Group, and comprehensive reservoir surveillance. Understanding the reservoir architecture of the Dupuy Formation is a key aspect to ensuring the success of the injection program. The Gorgon CO2 Baseline survey (BWI3D) was acquired in 2009 to provide a 4D baseline for ongoing CO2 monitoring and to improve reservoir characterization. Mapping of the survey has been integrated with neighboring 3D and 2D seismic surveys, geophysical well logs, core, image log, and biostratigraphic data to characterize the reservoir architecture. The Dupuy Formation in the Barrow Island area is a locally thick (~500m), sand-prone system deposited in a variety of deep water environments at the base of an active, steep slope. The Dupuy Formation has been sourced from the southeast, via a Late Jurassic submarine canyon. Basin-ward of Barrow Island the Dupuy Formation forms a classical lobate geometry consistent with the size, age and orientation of the canyon. The injection area is outboard of the canyon mouth in the transition from a weakly confined to unconfined distributary system. Some intervals have been heavily modified via Mass Transport Complexes (MTC) that have degraded reservoir quality and imparted irregular bathymetry that has influenced subsequent deposition. The prevalence of slumping and disturbed bedding is anticipated to assist CO2 containment by increasing flow path tortuosity and formation exposure. Intra-reservoir baffles appear limited in extent and the absence of confined channels is anticipated to promote an even plume front. The work presented here is broadly consistent with previously published models for the Kimmeridgian-Tithonian of the Carnarvon Basin and confirms the Dupuy Formation beneath Barrow Island is a good target for the disposal of the Gorgon Field reservoir carbon dioxide. The Kimmeridgian-Tithonian Dupuy Formation forms the reservoir for the Gorgon CO₂ injection project. The injection project will be one of the largest in the world, reducing greenhouse gas emissions from the Gorgon Project by approximately 40 percent. The Project plans to inject between 3.4 and 4.0 million tonnes of reservoir carbon dioxide each year. The project involves CO₂ injection, water production to manage reservoir pressure, water disposal into the overlying Barrow Group, and comprehensive reservoir surveillance. Understanding the reservoir architecture of the Dupuy Formation is a key aspect to ensuring the success of the injection program. The Gorgon CO₂ Baseline survey (BWI3D) was acquired in 2009 to provide a 4D baseline for ongoing CO₂ monitoring and to improve reservoir characterization. Mapping of the survey has been integrated with neighboring 3D and 2D seismic surveys, geophysical well logs, core, image log, and biostratigraphic data to characterize the reservoir architecture. The Dupuy Formation in the Barrow Island area is a locally thick (~500m), sand-prone system deposited in a variety of deep water environments at the base of an active, steep slope. The Dupuy Formation has been sourced from the southeast, via a Late Jurassic submarine canyon. Basin-ward of Barrow Island the Dupuy Formation forms a classical lobate geometry consistent with the size, age and orientation of the canyon. The injection area is outboard of the canyon mouth in the transition from a weakly confined to unconfined distributary system. Some intervals have been heavily modified via Mass Transport Complexes (MTC) that have degraded reservoir quality and imparted irregular bathymetry that has influenced subsequent deposition. The prevalence of slumping and disturbed bedding is anticipated to assist CO₂ containment by increasing flow path tortuosity and formation exposure. Intra-reservoir baffles appear limited in extent and the absence of confined channels is anticipated to promote an even plume front. The work presented here is broadly consistent with previously published models for the Kimmeridgian-Tithonian of the Carnarvon Basin and confirms the Dupuy Formation beneath Barrow Island is a good target for the disposal of the Gorgon Field reservoir carbon dioxide. Panel_15474 Panel_15474 10:10 AM 10:30 AM

The Farnsworth Unit in Ochiltree County, TX, is the site of the Southwest Partnership (SWP) on Carbon Sequestration's large-scale carbon capture, utilization, and storage experiment. A comprehensive 3D geologic model provides the basis for monitoring and modeling CO2 migration or leakage from the upper Morrow sandstone reservoir, which is undergoing tertiary recovery using anthropogenic CO2. The SWP acquired a 45 square mile 3D seismic survey over the entire Farnsworth Unit. Also acquired were vertical seismic profiles, wireline logs, and core data from three new wells. Formation top interpretations are based on integrating 3D seismic and compressional sonic well log data into a velocity model to convert the seismic z-axis into the depth-domain. Converting domains allowed the 3D seismic data to be correlated to other depth-domain datasets, such as new and legacy well log data and core sections. Surfaces generated from seismic interpretation also provided the framework for a geologic model that can be populated with information from seismic attributes and thus allows propagation of reservoir properties into the 3D seismic volume. Seismic attributes describe a measurable characteristic of seismic data that resolves features or quantifies some physical property. While fractures and faults are not always obvious in seismic data, edge enhancing seismic attributes can be employed to highlight those features. Coherency volumes that measure waveform similarity and ant-tracking volumes that track continuous features were generated to illuminate possible fault structures. Three faults were interpreted that were resolvable across different attributes and defined planar features in three dimensions. Seismic attributes are also useful for determining rock properties that can populate a 3D geomodel. Geometric attributes that are sensitive to reflection impedance changes help predict porosity, lithology, and formation thicknesses. Work is ongoing to propagate lithologically sensitive attributes to identify channels that could act as preferential fluid flow paths in the Morrow sandstone. The Farnsworth Unit in Ochiltree County, TX, is the site of the Southwest Partnership (SWP) on Carbon Sequestration's large-scale carbon capture, utilization, and storage experiment. A comprehensive 3D geologic model provides the basis for monitoring and modeling CO₂ migration or leakage from the upper Morrow sandstone reservoir, which is undergoing tertiary recovery using anthropogenic CO₂. The SWP acquired a 45 square mile 3D seismic survey over the entire Farnsworth Unit. Also acquired were vertical seismic profiles, wireline logs, and core data from three new wells. Formation top interpretations are based on integrating 3D seismic and compressional sonic well log data into a velocity model to convert the seismic z-axis into the depth-domain. Converting domains allowed the 3D seismic data to be correlated to other depth-domain datasets, such as new and legacy well log data and core sections. Surfaces generated from seismic interpretation also provided the framework for a geologic model that can be populated with information from seismic attributes and thus allows propagation of reservoir properties into the 3D seismic volume. Seismic attributes describe a measurable characteristic of seismic data that resolves features or quantifies some physical property. While fractures and faults are not always obvious in seismic data, edge enhancing seismic attributes can be employed to highlight those features. Coherency volumes that measure waveform similarity and ant-tracking volumes that track continuous features were generated to illuminate possible fault structures. Three faults were interpreted that were resolvable across different attributes and defined planar features in three dimensions. Seismic attributes are also useful for determining rock properties that can populate a 3D geomodel. Geometric attributes that are sensitive to reflection impedance changes help predict porosity, lithology, and formation thicknesses. Work is ongoing to propagate lithologically sensitive attributes to identify channels that could act as preferential fluid flow paths in the Morrow sandstone. Panel_15473 Panel_15473 10:30 AM 10:50 AM

If carbon storage is to be implemented at a potential storage site at the Rock Springs Uplift (southwest Wyoming), there are significant challenges to overcome regarding sealing assessment. Specifically, identifying the potential for leakage of CO2 along natural bypass systems such as faults and fractures. This study evaluates the integrity of strata at a University of Wyoming test well (RSU #1 049-047-07154) using a 25 square mile 3-D survey adjacent to the well. Specifically, we focus on determining potential seal bypass systems using multiple seismic attributes. Two groups of seal bypass systems were recognized within the seismic survey bounds; (1) dispersed sets of orthogonal deformation bands and faults, and (2) isolated fractures and chimneys likely associated with karst collapse features. Deformation bands are associated with folding of the Paleozoic strata and are arranged in patterns related to regional structural deformation. Fracture analysis reveal that lineaments within the study area strike northeast-southwest and northwest-southeast. This observation is consistent with joint orientation in surface outcrops. Isolated, vertically oriented fractures that originate in the Mississippian Madison Limestone were interpreted on coherency horizon slices and within the Rock Integrity attribute volume. These features may result from karst processes such as dissolution, hydrothermal alteration, tectonism, or a combination of these processes. Continuous spectral analysis of wireline logs from the RSU #1 well were used to describe porosity heterogeneity at an intermediate scale of several feet to tens of feet. We found that spectrograms generate useful information that can be utilized for identification of intervals with variable reservoir/sealing capacity within a formation. The amplitude and distribution of spectral peaks appears to correspond with the relative effectiveness of confining layers. Based on the above data, multiple sealing lithologies were identified at the study site though some were associated with seal bypass systems. Additional unknowns include compartmentalization of the reservoirs along fault boundaries and the risk factors for induced seismicity along existing faults and fractures. Hence, it is of great importance to choose reliable rock properties for simulation modeling and, if possible, increase the amount of available subsurface data. If carbon storage is to be implemented at a potential storage site at the Rock Springs Uplift (southwest Wyoming), there are significant challenges to overcome regarding sealing assessment. Specifically, identifying the potential for leakage of CO₂ along natural bypass systems such as faults and fractures. This study evaluates the integrity of strata at a University of Wyoming test well (RSU #1 049-047-07154) using a 25 square mile 3-D survey adjacent to the well. Specifically, we focus on determining potential seal bypass systems using multiple seismic attributes. Two groups of seal bypass systems were recognized within the seismic survey bounds; (1) dispersed sets of orthogonal deformation bands and faults, and (2) isolated fractures and chimneys likely associated with karst collapse features. Deformation bands are associated with folding of the Paleozoic strata and are arranged in patterns related to regional structural deformation. Fracture analysis reveal that lineaments within the study area strike northeast-southwest and northwest-southeast. This observation is consistent with joint orientation in surface outcrops. Isolated, vertically oriented fractures that originate in the Mississippian Madison Limestone were interpreted on coherency horizon slices and within the Rock Integrity attribute volume. These features may result from karst processes such as dissolution, hydrothermal alteration, tectonism, or a combination of these processes. Continuous spectral analysis of wireline logs from the RSU #1 well were used to describe porosity heterogeneity at an intermediate scale of several feet to tens of feet. We found that spectrograms generate useful information that can be utilized for identification of intervals with variable reservoir/sealing capacity within a formation. The amplitude and distribution of spectral peaks appears to correspond with the relative effectiveness of confining layers. Based on the above data, multiple sealing lithologies were identified at the study site though some were associated with seal bypass systems. Additional unknowns include compartmentalization of the reservoirs along fault boundaries and the risk factors for induced seismicity along existing faults and fractures. Hence, it is of great importance to choose reliable rock properties for simulation modeling and, if possible, increase the amount of available subsurface data. Panel_15469 Panel_15469 10:50 AM 11:10 AM

Monitoring CO2 injection for enhanced hydrocarbon recovery in carbonate reservoirs poses a technical challenge interpreting changes in pressure & fluid saturations away from wells. The present study focuses on quantitative rock physics modeling of time-lapse (4D) changes in reservoir pressure and multi-fluid saturations in a carbonate reservoir from southern Canada. The field is currently under WAG (Water Alternate Gas) injection, and both pressure and CO2 saturation change during the CO2 flooding process. The goal of the dynamic reservoir modeling is to understand and predict CO2 saturations over the reservoir. To achieve this goal, we modeled reservoir properties at different fluid saturations with various effective pressure regimes. 4D rock physics analysis provides the link between dynamic reservoir properties and 4D seismic responses. We calculated elastic properties of fluid mixtures (brine, oil, and CO2) at different pressures, based on a constant reservoir temperature of 600C, as the WAG injection does not significantly alter temperatures in the reservoir. Initially, effective properties of the brine saturated reservoir are measured at the original pressure (15MPa). Then, we replace the brine fluid with different mixture of fluids and calculate effective properties of the reservoir at different expected pressure values. These elastic properties (incompressibility and rigidity) are affected by changes in the pressure for the same fluid saturation. Modeling results show a significant change (around 30-40% decrease) in the impedance for fluid saturation when the reservoir is saturated with CO2 compared to the brine-saturated case. 4D rock physics models demonstrated that, at reservoir level, Lambda-Rho highly correlate with changes in fluid saturation, with lowest values when the reservoir is saturated with CO2. Likewise, Mu-Rho, highly correlated with reservoir pressure, is higher as the effective pressure increases. During WAG injection, it is expected that changes in CO2 saturation are more prominent compared to changes in effective pressure away from injection wells. Monitoring CO₂ injection for enhanced hydrocarbon recovery in carbonate reservoirs poses a technical challenge interpreting changes in pressure & fluid saturations away from wells. The present study focuses on quantitative rock physics modeling of time-lapse (4D) changes in reservoir pressure and multi-fluid saturations in a carbonate reservoir from southern Canada. The field is currently under WAG (Water Alternate Gas) injection, and both pressure and CO₂ saturation change during the CO₂ flooding process. The goal of the dynamic reservoir modeling is to understand and predict CO₂ saturations over the reservoir. To achieve this goal, we modeled reservoir properties at different fluid saturations with various effective pressure regimes. 4D rock physics analysis provides the link between dynamic reservoir properties and 4D seismic responses. We calculated elastic properties of fluid mixtures (brine, oil, and CO₂) at different pressures, based on a constant reservoir temperature of 600C, as the WAG injection does not significantly alter temperatures in the reservoir. Initially, effective properties of the brine saturated reservoir are measured at the original pressure (15MPa). Then, we replace the brine fluid with different mixture of fluids and calculate effective properties of the reservoir at different expected pressure values. These elastic properties (incompressibility and rigidity) are affected by changes in the pressure for the same fluid saturation. Modeling results show a significant change (around 30-40% decrease) in the impedance for fluid saturation when the reservoir is saturated with CO₂ compared to the brine-saturated case. 4D rock physics models demonstrated that, at reservoir level, Lambda-Rho highly correlate with changes in fluid saturation, with lowest values when the reservoir is saturated with CO₂. Likewise, Mu-Rho, highly correlated with reservoir pressure, is higher as the effective pressure increases. During WAG injection, it is expected that changes in CO₂ saturation are more prominent compared to changes in effective pressure away from injection wells. Panel_15471 Panel_15471 11:10 AM 11:30 AM

To understand the interaction of CO2 and sandstone saturated formation water after CO2 injection under reservoir condition, we designed two sets of CO2-displacement experiments. The first experiment (oil-free) uses arkose sandstone saturated with formation water, while the second experiment (oil-bearing) uses arkose sandstone containing both formation water and oil . Both experiments were undertaken at the same P-T condition. Compared with the oil-free sandstone experiment, the presence of oil can substantially reduce the reaction degree between fluid with CO2 and sensitive minerals. The corrosion rates of the K-feldspar and the carbonate minerals for the oil-bearing experiment are 1/5 and 1/4 of that for the oil-free experiments, respectively. For the silicate minerals represented by the K-feldspar, the presence of oil mainly delays the corrosion in the experiment, and reduces the equilibrium corrosion rate. For the carbonate minerals, the presence of oil mainly affects the corrosion at the beginning of the experiments, and reduces the corrosion rate once it reaches to its maximum. The core permeability is reduced after the CO2-water flooding for both the oil-free and oil-bearing cases. The reduction in permeability resulted from the presence of clay particles released by the dissolution of the carbonate cement, which travel in the fluid flow path and accumulate at pore throats. The results provide new insights into CO2 trapping mechanisms in depleted oil and gas reservoirs, and into the potential formation damage that may result from massive injections of CO2 into reservoirs during enhanced oil recovery programs. To understand the interaction of CO₂ and sandstone saturated formation water after CO₂ injection under reservoir condition, we designed two sets of CO₂-displacement experiments. The first experiment (oil-free) uses arkose sandstone saturated with formation water, while the second experiment (oil-bearing) uses arkose sandstone containing both formation water and oil . Both experiments were undertaken at the same P-T condition. Compared with the oil-free sandstone experiment, the presence of oil can substantially reduce the reaction degree between fluid with CO₂ and sensitive minerals. The corrosion rates of the K-feldspar and the carbonate minerals for the oil-bearing experiment are 1/5 and 1/4 of that for the oil-free experiments, respectively. For the silicate minerals represented by the K-feldspar, the presence of oil mainly delays the corrosion in the experiment, and reduces the equilibrium corrosion rate. For the carbonate minerals, the presence of oil mainly affects the corrosion at the beginning of the experiments, and reduces the corrosion rate once it reaches to its maximum. The core permeability is reduced after the CO₂-water flooding for both the oil-free and oil-bearing cases. The reduction in permeability resulted from the presence of clay particles released by the dissolution of the carbonate cement, which travel in the fluid flow path and accumulate at pore throats. The results provide new insights into CO₂ trapping mechanisms in depleted oil and gas reservoirs, and into the potential formation damage that may result from massive injections of CO₂ into reservoirs during enhanced oil recovery programs. Panel_15479 Panel_15479 11:30 AM 11:50 AM

Paul "Mitch" Harris hails from West Virginia University where he earned his BS and MS in Geology. Mitch migrated to the University of Miami, for his PhD where he focused on the sequence of modern sediments. Mitch joined Getty Oil briefly then Gulf Oil until they merged with Chevron and Mitch moved to California. Mitch has spent his career thus far linking modern and ancient systems and has worked everything from the Permian Basin to Super Giants like Tengiz, while making countless trips to the modern to teach, ask questions, observe and apply concepts to the subsurface. Mitch is adjunct professor at the University of Miami and Rice. In 2010-2011, Mitch served as President of SEPM, and he’s been awarded SEPM Honorary Membership, Honorary Life Award from PBSEPM, AAPG Honorary Membership, Wallace E. Pratt Memorial Award, Robert H.Dott, Sr. Memorial Award twice and John W. Shelton Search & Discovery Award.

Paul "Mitch" Harris hails from West Virginia University where he earned his BS and MS in Geology. Mitch migrated to the University of Miami, for his PhD where he focused on the sequence of modern sediments. Mitch joined Getty Oil briefly then Gulf Oil until they merged with Chevron and Mitch moved to California. Mitch has spent his career thus far linking modern and ancient systems and has worked everything from the Permian Basin to Super Giants like Tengiz, while making countless trips to the modern to teach, ask questions, observe and apply concepts to the subsurface. Mitch is adjunct professor at the University of Miami and Rice. In 2010-2011, Mitch served as President of SEPM, and he’s been awarded SEPM Honorary Membership, Honorary Life Award from PBSEPM, AAPG Honorary Membership, Wallace E. Pratt Memorial Award, Robert H.Dott, Sr. Memorial Award twice and John W. Shelton Search & Discovery Award.

Panel_14392 Panel_14392 1:15 PM 5:05 PM

Panel_15765 Panel_15765 1:15 PM 12:00 AM

Oolitic, peloidal, and skeletal grainstones are a key element of carbonate reservoir heterogeneity in many ramp crest and shelf-margin settings. Imaging the aerial and vertical (stratigraphic) distribution of grainstone geobodies is essential for understanding distribution of primary and secondary porosity and fluid flow pathways in reservoirs like the prolific San Andres/Grayburg and Horseshoe Atoll trends of the Permian Basin. Typical grainstone elements are contained within individual depositional cycles of 2-10 m thickness. When stacked vertically there is an opportunity to image these seismically, but commonly intermediate-scale landward or seaward translation of facies tracts keeps porosity zones thin and distributed, thus below seismic resolution. Modern examples like the well-documented Joulter’s Cay complex described by Harris (1979) highlight the complexity of these deposits in both time and space, and detailed outcrop mapping of successive intra-cycle bar complexes demonstrates a range of dip-extents rarely > 1 km. Outcrop and subsurface studies of Paleozoic (14) and Mesozoic (7) outcrops and reservoirs (each averaging 10 discrete grainstone geobodies) highlight differences between land-attached and shelf-edge complexes. Land-attached grainstone geobodies include foreshore-shoreface, lagoon-inlet-barrier, and sharp-based shoreface. Fair-weather and storm waves provide current energy; wind-driven longshore currents are secondary. Shelf-edge grainstones include back-reef aprons (skeletal only), tidal bars (oolitic), mixed tide-wave systems, and wind-wave bars. The most extensive ancient examples have a strong tidal influence, stable tectonics and minimal eustatic signal. The presence of a shelf-interior lagoon to allow tidal exchange is critical, and persistent longshore or trade-wind current dominates some settings. Tide-dominated grainstones show complex paleocurrents with distinct ebb-domination, large (>1m) bedforms, and oolitic composition. The Ambergris shoal (Caicos) is an analog for low-energy grainstones with maximum 10-20 cm cross-bed size such as the Jurassic Arab D. Storm-ridge wave-dominated grainstones like the shelf-crest of the Capitan system and the caprinid beaches of the Stuart City trend are characteristically coarse-grained, have significant vadose profiles, and are distinctly strike-elongate and dip limited. Tuning next-generation stochastic models to these depositional assemblages should constrain the universe of realizations. Oolitic, peloidal, and skeletal grainstones are a key element of carbonate reservoir heterogeneity in many ramp crest and shelf-margin settings. Imaging the aerial and vertical (stratigraphic) distribution of grainstone geobodies is essential for understanding distribution of primary and secondary porosity and fluid flow pathways in reservoirs like the prolific San Andres/Grayburg and Horseshoe Atoll trends of the Permian Basin. Typical grainstone elements are contained within individual depositional cycles of 2-10 m thickness. When stacked vertically there is an opportunity to image these seismically, but commonly intermediate-scale landward or seaward translation of facies tracts keeps porosity zones thin and distributed, thus below seismic resolution. Modern examples like the well-documented Joulter’s Cay complex described by Harris (1979) highlight the complexity of these deposits in both time and space, and detailed outcrop mapping of successive intra-cycle bar complexes demonstrates a range of dip-extents rarely > 1 km. Outcrop and subsurface studies of Paleozoic (14) and Mesozoic (7) outcrops and reservoirs (each averaging 10 discrete grainstone geobodies) highlight differences between land-attached and shelf-edge complexes. Land-attached grainstone geobodies include foreshore-shoreface, lagoon-inlet-barrier, and sharp-based shoreface. Fair-weather and storm waves provide current energy; wind-driven longshore currents are secondary. Shelf-edge grainstones include back-reef aprons (skeletal only), tidal bars (oolitic), mixed tide-wave systems, and wind-wave bars. The most extensive ancient examples have a strong tidal influence, stable tectonics and minimal eustatic signal. The presence of a shelf-interior lagoon to allow tidal exchange is critical, and persistent longshore or trade-wind current dominates some settings. Tide-dominated grainstones show complex paleocurrents with distinct ebb-domination, large (>1m) bedforms, and oolitic composition. The Ambergris shoal (Caicos) is an analog for low-energy grainstones with maximum 10-20 cm cross-bed size such as the Jurassic Arab D. Storm-ridge wave-dominated grainstones like the shelf-crest of the Capitan system and the caprinid beaches of the Stuart City trend are characteristically coarse-grained, have significant vadose profiles, and are distinctly strike-elongate and dip limited. Tuning next-generation stochastic models to these depositional assemblages should constrain the universe of realizations. Panel_14757 Panel_14757 1:20 PM 1:40 PM

To assess prospective modeling parameters and trends for oolitic tidal sand shoals, this study examines the cycle-scale architecture of the mobile, oolitic tidal bar belt at Schooner Cays, Bahamas. Process-based, stratigraphic trends are captured in quantitative, geocellular models of the shoal from analyses of satellite imagery, 2-D high-frequency seismic (Chirp), and sediment cores. Observations reveal recurring trends in geomorphic shapes and sedimentation patterns across this oolitic bar belt. For example, longitudinal tidal sand ridges repetitively extend up to 8 km along depositional dip gradually transforming backward into channel-bound, compound barforms consisting of linear, parabolic, and shoulder bars before terminating into a laterally extensive (<10 km), strike-elongate, sand sheet. Detailed geologic models of the shoal integrate facies probability curves, facies probability maps, facies probability cubes, bar and channel centerlines, locally varying azimuthal trends, satellite imagery, 2-D seismic, and core. To enhance confidence in this approach, we first quantify and demonstrate spatial trends in grain size, type, sorting, and barform orientation across the ooid shoal. A geocellular facies model—conditioned to multiple 3-D trends across the shoal—is built from which end-member barforms are extracted for 3-D visualization, quantitative analyses, and validation of geostatistical trends at different scales. Co-rendering of satellite imagery and bathymetric grids reveals that barforms are largely low-angle (<6°) and laterally gradational with adjacent shoal environments. As such, sequential indicator simulation (SIS) techniques are preferred. Facies proportion curves are well-ordered with respect to water depth facilitating distribution of upward-shallowing trends within barforms across the shoal. Inclusion of geometrical trends, anisotropic variograms, and 3-D facies probability grids during SIS generates gradational lithofacies tracts that are appropriately juxtaposed and consistently elongate parallel to bar crests and channels. Analyses of bootstrapped end-member barforms validates modeling techniques and reveals locally predicted facies distributions consistent with field and core observations. Although the modeling trends and methods presented here are for a specific style of modern oolitic sand shoal, similar trends might be discovered for ancient oolitic reservoirs through integrative studies of core and advanced seismic attributes. To assess prospective modeling parameters and trends for oolitic tidal sand shoals, this study examines the cycle-scale architecture of the mobile, oolitic tidal bar belt at Schooner Cays, Bahamas. Process-based, stratigraphic trends are captured in quantitative, geocellular models of the shoal from analyses of satellite imagery, 2-D high-frequency seismic (Chirp), and sediment cores. Observations reveal recurring trends in geomorphic shapes and sedimentation patterns across this oolitic bar belt. For example, longitudinal tidal sand ridges repetitively extend up to 8 km along depositional dip gradually transforming backward into channel-bound, compound barforms consisting of linear, parabolic, and shoulder bars before terminating into a laterally extensive (<10 km), strike-elongate, sand sheet. Detailed geologic models of the shoal integrate facies probability curves, facies probability maps, facies probability cubes, bar and channel centerlines, locally varying azimuthal trends, satellite imagery, 2-D seismic, and core. To enhance confidence in this approach, we first quantify and demonstrate spatial trends in grain size, type, sorting, and barform orientation across the ooid shoal. A geocellular facies model—conditioned to multiple 3-D trends across the shoal—is built from which end-member barforms are extracted for 3-D visualization, quantitative analyses, and validation of geostatistical trends at different scales. Co-rendering of satellite imagery and bathymetric grids reveals that barforms are largely low-angle (<6°) and laterally gradational with adjacent shoal environments. As such, sequential indicator simulation (SIS) techniques are preferred. Facies proportion curves are well-ordered with respect to water depth facilitating distribution of upward-shallowing trends within barforms across the shoal. Inclusion of geometrical trends, anisotropic variograms, and 3-D facies probability grids during SIS generates gradational lithofacies tracts that are appropriately juxtaposed and consistently elongate parallel to bar crests and channels. Analyses of bootstrapped end-member barforms validates modeling techniques and reveals locally predicted facies distributions consistent with field and core observations. Although the modeling trends and methods presented here are for a specific style of modern oolitic sand shoal, similar trends might be discovered for ancient oolitic reservoirs through integrative studies of core and advanced seismic attributes. Panel_14759 Panel_14759 1:40 PM 2:00 PM

Great Bahama Bank (GBB) is ‘the’ modern example of a flat-topped, isolated carbonate platform. It is a major modern location of non-skeletal carbonate deposition that stands behind much of our understanding of modern processes of carbonate sedimentation and is the basis for geological models that serve as reservoir analogs. GBB provides valuable insight into the extent and patterns of sediment fill of accommodation space across the platform top. Satellite imagery (Landsat TM and ETM+) and an extensive set of water-depth measurements (n = 5,723) were used to map bathymetry across GBB. Analysis of the resulting digital terrain model (DTM) reveals the maximum variation in depth-elevation over this vast (>100,000 sq. km) platform extends from the -30 m platform break to the highest Pleistocene eolianite ridge of 63 m on Cat Island. It is noteworthy, however, that although islands atop the GBB are numerous (n = 1,427) they occupy only 7.5%, or 7,716 sq. km, of the platform-top. Since islands represent the portion of the platform where accommodation has been overfilled, their rarity emphasizes the challenges to filling accommodation space across such a large platform despite the diverse grain factories producing carbonate detritus atop GBB (mud precipitation through whitings, ooids along the platform margins, skeletal sediments, and non-skeletal grains such as pellets, peloids and aggregate grains). It should be noted that aerial coverage of the GBB’s islands is in fact an overestimate of overfilled accommodation; although many Holocene islands are built from storm ridge and eolianite deposits, the contribution of sub-tidal facies deposited during higher sea level are also important structuring components to Pleistocene islands. Considering the bathymetric variation of the GBB, the DTM brings to light the fact that only 7% (7,237 sq. km) of the awash platform has aggraded to sea level in the form of sand shoals or mud flats (<1 m water depth) and therefore the majority of available accommodation (~87,600 sq. km or > 85% of the platform top) remains under-filled with sediment. Areas of filled accommodation mostly extend platformward from the westerly coastlines of islands, which in turn are preferentially distributed along the eastern (windward) margin of the GBB. The bathymetric patterns highlight the irregular filling of accommodation space and graphically emphasize the challenges of correlating depositional cycles of variable thickness across a platform. Great Bahama Bank (GBB) is ‘the’ modern example of a flat-topped, isolated carbonate platform. It is a major modern location of non-skeletal carbonate deposition that stands behind much of our understanding of modern processes of carbonate sedimentation and is the basis for geological models that serve as reservoir analogs. GBB provides valuable insight into the extent and patterns of sediment fill of accommodation space across the platform top. Satellite imagery (Landsat TM and ETM+) and an extensive set of water-depth measurements (n = 5,723) were used to map bathymetry across GBB. Analysis of the resulting digital terrain model (DTM) reveals the maximum variation in depth-elevation over this vast (>100,000 sq. km) platform extends from the -30 m platform break to the highest Pleistocene eolianite ridge of 63 m on Cat Island. It is noteworthy, however, that although islands atop the GBB are numerous (n = 1,427) they occupy only 7.5%, or 7,716 sq. km, of the platform-top. Since islands represent the portion of the platform where accommodation has been overfilled, their rarity emphasizes the challenges to filling accommodation space across such a large platform despite the diverse grain factories producing carbonate detritus atop GBB (mud precipitation through whitings, ooids along the platform margins, skeletal sediments, and non-skeletal grains such as pellets, peloids and aggregate grains). It should be noted that aerial coverage of the GBB’s islands is in fact an overestimate of overfilled accommodation; although many Holocene islands are built from storm ridge and eolianite deposits, the contribution of sub-tidal facies deposited during higher sea level are also important structuring components to Pleistocene islands. Considering the bathymetric variation of the GBB, the DTM brings to light the fact that only 7% (7,237 sq. km) of the awash platform has aggraded to sea level in the form of sand shoals or mud flats (<1 m water depth) and therefore the majority of available accommodation (~87,600 sq. km or > 85% of the platform top) remains under-filled with sediment. Areas of filled accommodation mostly extend platformward from the westerly coastlines of islands, which in turn are preferentially distributed along the eastern (windward) margin of the GBB. The bathymetric patterns highlight the irregular filling of accommodation space and graphically emphasize the challenges of correlating depositional cycles of variable thickness across a platform. Panel_14764 Panel_14764 2:00 PM 2:20 PM

The Bahamian archipelago is considered tectonically inactive but a fold growth analysis on the most distal anticline of the Cuban fold and thrust belt indicates continuous shortening throughout the Neogene. In addition, several structural elements around of Cay Sal Bank document recent movements. Deep-rooted faults with both thrust and wrench fault characteristics separate the platform from the adjacent basin. Two of these faults reach the seafloor, forming 30 km long and 50 m high scars on the seafloor. Anticlines that are dissected by faults display Holocene fold-growth strata. Both these features, together with recent earthquakes, document the neo-tectonic activity in this part of the archipelago. Multi-channel seismic and multi-beam data reveal for the first time a tectonic influence on the slope sedimentation of Great Bahama Bank (GBB) and Cay Sal Bank (CSB). Neo-tectonics does not change the general bank morphology but it is reflected in the slope development. GBB with its 450 km long margin that is nearly perpendicular to the Cuban fold and thrust belt displays the decreasing tectonic influence from south to north. In the proximity of the fold and thrust belt, large margin collapse features and associated mass transport complexes are common. Away from plate boundary only slope failures are observed that are likely not triggered by tectonic processes. Along eastern CSB the neo-tectonic activity is recognized in lateral displacements of slope canyons and vertical scars on the sea floor. On the north and eastern side of CSB, multichannel seismic data display deep-rooted faults terminating at various stratigraphic horizons, documenting the ongoing deformation related to the Cuban fold and thrust belt. Some of the faults displace the seafloor on the slope and in the basin. Bathymetric maps of the slopes display asymmetric canyons that are oriented oblique to smaller slope gullies and are in some places displaced laterally. This canyon geometry is interpreted to reflect an underlying fault pattern. The connection of faults to large mass wasting events is seen on seismic data where chaotic slump units terminate against buried faults. These slow tectonic movements in the Cuban fold and thrust belt are not enough to change overall platform architecture but influences the type and location of slope and margin failure. The Bahamian archipelago is considered tectonically inactive but a fold growth analysis on the most distal anticline of the Cuban fold and thrust belt indicates continuous shortening throughout the Neogene. In addition, several structural elements around of Cay Sal Bank document recent movements. Deep-rooted faults with both thrust and wrench fault characteristics separate the platform from the adjacent basin. Two of these faults reach the seafloor, forming 30 km long and 50 m high scars on the seafloor. Anticlines that are dissected by faults display Holocene fold-growth strata. Both these features, together with recent earthquakes, document the neo-tectonic activity in this part of the archipelago. Multi-channel seismic and multi-beam data reveal for the first time a tectonic influence on the slope sedimentation of Great Bahama Bank (GBB) and Cay Sal Bank (CSB). Neo-tectonics does not change the general bank morphology but it is reflected in the slope development. GBB with its 450 km long margin that is nearly perpendicular to the Cuban fold and thrust belt displays the decreasing tectonic influence from south to north. In the proximity of the fold and thrust belt, large margin collapse features and associated mass transport complexes are common. Away from plate boundary only slope failures are observed that are likely not triggered by tectonic processes. Along eastern CSB the neo-tectonic activity is recognized in lateral displacements of slope canyons and vertical scars on the sea floor. On the north and eastern side of CSB, multichannel seismic data display deep-rooted faults terminating at various stratigraphic horizons, documenting the ongoing deformation related to the Cuban fold and thrust belt. Some of the faults displace the seafloor on the slope and in the basin. Bathymetric maps of the slopes display asymmetric canyons that are oriented oblique to smaller slope gullies and are in some places displaced laterally. This canyon geometry is interpreted to reflect an underlying fault pattern. The connection of faults to large mass wasting events is seen on seismic data where chaotic slump units terminate against buried faults. These slow tectonic movements in the Cuban fold and thrust belt are not enough to change overall platform architecture but influences the type and location of slope and margin failure. Panel_14758 Panel_14758 2:20 PM 2:40 PM

Panel_15766 Panel_15766 2:40 PM 12:00 AM

Carbonate strata form important reservoirs in southeast Asia, including Eocene-Miocene isolated buildups. Although seismic data from some platforms illustrate internal geometries such as platformward progradation of reef sand aprons, in most, such direct facies indicators are absent. In such scenarios, analogs provide both conceptual models and data to constrain facies dimensions, orientation, and configuration. The overall objective of this study is to use remote sensing data to systematically examine and quantify spatial facies patterns of Holocene isolated carbonate buildups (ICB) in the South China Sea. The fundamental data for the study are high-resolution (<2.4 m2 multispectral, 0.6 m2 panchromatic) remote sensing images of 27 ICB. Each ICB is captured by at least one image collected between 2003 and 2014; 11 ICB include two or more temporally distinct images that permit assessing temporal changes on these platforms. Analysis of remote sensing data of ICB of the South China Sea includes platforms ranging in size from 5 – 195 km2, and include circular, ovoid, and elongate shapes. The mean orientation of the long axis for ICB of both the Spratly (73°) and the Paracel (96°) chains are slightly different, probably related to tectonic framework. ICB facies bodies include reefs and reef sand aprons that are non-uniformly distributed within and among platforms. Platforms range from incipiently drowned to almost fully aggraded, and include reef sand aprons and reefs that can exceed 1500 m width. Despite the variability, a pronounced trend of marked asymmetry of the spatial distribution reef sand aprons is evident: 89% of ICB include the widest reef sand apron on the north- or west-facing flank. These systems are not static. Although some ICB show no changes between multi-temporal images, several ICB illustrate rather pronounced changes; in one case (Mischief), reef-derived debris migrated over 300 m towards the platform interior in 8 years (2004-2012). A database of processes (characteristics of waves, tides, currents, and winds, for example) provides a process-based understanding of the genesis and potential evolution of these systems. These results provide conceptual models and data that could be used as input on facies attributes for geologic models. Carbonate strata form important reservoirs in southeast Asia, including Eocene-Miocene isolated buildups. Although seismic data from some platforms illustrate internal geometries such as platformward progradation of reef sand aprons, in most, such direct facies indicators are absent. In such scenarios, analogs provide both conceptual models and data to constrain facies dimensions, orientation, and configuration. The overall objective of this study is to use remote sensing data to systematically examine and quantify spatial facies patterns of Holocene isolated carbonate buildups (ICB) in the South China Sea. The fundamental data for the study are high-resolution (<2.4 m2 multispectral, 0.6 m2 panchromatic) remote sensing images of 27 ICB. Each ICB is captured by at least one image collected between 2003 and 2014; 11 ICB include two or more temporally distinct images that permit assessing temporal changes on these platforms. Analysis of remote sensing data of ICB of the South China Sea includes platforms ranging in size from 5 – 195 km², and include circular, ovoid, and elongate shapes. The mean orientation of the long axis for ICB of both the Spratly (73°) and the Paracel (96°) chains are slightly different, probably related to tectonic framework. ICB facies bodies include reefs and reef sand aprons that are non-uniformly distributed within and among platforms. Platforms range from incipiently drowned to almost fully aggraded, and include reef sand aprons and reefs that can exceed 1500 m width. Despite the variability, a pronounced trend of marked asymmetry of the spatial distribution reef sand aprons is evident: 89% of ICB include the widest reef sand apron on the north- or west-facing flank. These systems are not static. Although some ICB show no changes between multi-temporal images, several ICB illustrate rather pronounced changes; in one case (Mischief), reef-derived debris migrated over 300 m towards the platform interior in 8 years (2004-2012). A database of processes (characteristics of waves, tides, currents, and winds, for example) provides a process-based understanding of the genesis and potential evolution of these systems. These results provide conceptual models and data that could be used as input on facies attributes for geologic models. Panel_14760 Panel_14760 3:25 PM 3:45 PM

The sedimentary record of New Providence Platform (NPP) and the Exumas windward margin portions of Great Bahama Bank reveals complex, shifting sediment patterns during the Holocene sea-level transgression. Understanding these patterns provides a more robust analog for interpreting and correlating depositional cycles in subsurface examples. Sea-level changes drive sediment dynamics in shallow-water carbonate settings, producing facies indicative of relative sea-level positions and making them excellent sea-level archives. Rising sea level and concomitant sedimentation constantly change the energy distribution and locations of sedimentation and erosion. A shift in the energy balance across NPP during the Holocene transgression is recorded in the coarsening-upwards sedimentary succession documented in the platform interior (Yellow Banks). This succession indicates an increase in energy with increasing water depth, changing the once restricted platform to high-energy, open-marine conditions (i.e. change from muddy to high-energy, grapestone/skeletal sediments). The preservation potential varies from the platform interior (highest preservation potential) eastwards towards the outermost Exuma Cays platform margin (poorest preservation potential). The Exumas windward platform margin features islands dissected by high-energy channels and ooid shoals. Pleistocene antecedent topography acts as a barrier to the erosion caused by the Holocene transgression and also provides a template for complex Holocene carbonate sediment deposition and accretion. Eastward of the islands, very little Holocene sediment is preserved; sediments on this sloping margin are either transported towards the platform or into Exuma Sound. In many places, the sloping outer margin is eroded down to the Pleistocene surface. Locally, the windward margins of the islands contain steep, eroding sea cliffs and small relicts of older Holocene eolianites. On leeward sides of the islands towards the platform interior, the erosion is minimal and a more complete record of Holocene sedimentation is commonly present. The Pleistocene islands mark the boundary between low and high sediment preservation. In addition, in the present-day energy situation, they are also focusing the tidal currents, producing high-energy environments with increased sedimentation. These sediments are deposited in ooid shoals or as accreting beaches on both the open-ocean and the bankside of the Pleistocene islands. The sedimentary record of New Providence Platform (NPP) and the Exumas windward margin portions of Great Bahama Bank reveals complex, shifting sediment patterns during the Holocene sea-level transgression. Understanding these patterns provides a more robust analog for interpreting and correlating depositional cycles in subsurface examples. Sea-level changes drive sediment dynamics in shallow-water carbonate settings, producing facies indicative of relative sea-level positions and making them excellent sea-level archives. Rising sea level and concomitant sedimentation constantly change the energy distribution and locations of sedimentation and erosion. A shift in the energy balance across NPP during the Holocene transgression is recorded in the coarsening-upwards sedimentary succession documented in the platform interior (Yellow Banks). This succession indicates an increase in energy with increasing water depth, changing the once restricted platform to high-energy, open-marine conditions (i.e. change from muddy to high-energy, grapestone/skeletal sediments). The preservation potential varies from the platform interior (highest preservation potential) eastwards towards the outermost Exuma Cays platform margin (poorest preservation potential). The Exumas windward platform margin features islands dissected by high-energy channels and ooid shoals. Pleistocene antecedent topography acts as a barrier to the erosion caused by the Holocene transgression and also provides a template for complex Holocene carbonate sediment deposition and accretion. Eastward of the islands, very little Holocene sediment is preserved; sediments on this sloping margin are either transported towards the platform or into Exuma Sound. In many places, the sloping outer margin is eroded down to the Pleistocene surface. Locally, the windward margins of the islands contain steep, eroding sea cliffs and small relicts of older Holocene eolianites. On leeward sides of the islands towards the platform interior, the erosion is minimal and a more complete record of Holocene sedimentation is commonly present. The Pleistocene islands mark the boundary between low and high sediment preservation. In addition, in the present-day energy situation, they are also focusing the tidal currents, producing high-energy environments with increased sedimentation. These sediments are deposited in ooid shoals or as accreting beaches on both the open-ocean and the bankside of the Pleistocene islands. Panel_14763 Panel_14763 3:45 PM 4:05 PM

Characterizing diagenesis, in addition to facies arrangements and stratigraphic architecture, is critical for predicting the distribution of reservoir quality in many carbonate reservoirs. Carbonate diagenetic histories are often extremely complex, reflecting syndepositional to deep burial processes with multiple superimposed cementation and dissolution events. Traditionally, these records are captured in paragenetic charts that focus only on the presence of the various phases in a rock but lack linkage to reservoir quality. We here propose an approach for carbonate diagenetic characterization that, in addition to traditional documentation of the paragenetic sequence of cements and pore types, also 1) distills the multifaceted paragenesis into the event(s) that most impacted present-day reservoir quality (Key Paragenetic Step, KPS); 2) graphically depicts the starting point, diagenetic path, and end-product for a particular rock (Paragenogram); and 3) links to the distribution of reservoir quality (flow units) through integration of diagenetic profiles, cumulative-thickness plots, depositional facies, and sequence stratigraphy. To demonstrate this approach, we present examples from carbonate margin and slope facies of the Paleozoic Tengiz field in the Republic of Kazakhstan, where a complex diagenetic history heavily impacted matrix reservoir quality and non-matrix flow characteristics. The dataset consists of 16 cores with thin sections that sample margin grainstone/boundstone-, upper slope boundstone-, middle slope breccia/grainstone-, and lower slope grainstone/mudstone facies assemblages. Using our new approach, we developed a framework that ties diagenetic styles to resulting rock types and improves the linkages between depositional facies, diagenetic overprints, volumetrically significant pore families, and the origins and distribution of enhanced matrix reservoir quality. For example, this work underscored the importance of burial dissolution and its link to improved matrix porosity, permeability, and flow behavior. These findings provide geological context to better understand MICP-derived pore throat data, porosity-permeability distributions, and vertical flow behavior along the borehole, as well as valuable input for log-based Petrophysical Rock Typing. Characterizing diagenesis, in addition to facies arrangements and stratigraphic architecture, is critical for predicting the distribution of reservoir quality in many carbonate reservoirs. Carbonate diagenetic histories are often extremely complex, reflecting syndepositional to deep burial processes with multiple superimposed cementation and dissolution events. Traditionally, these records are captured in paragenetic charts that focus only on the presence of the various phases in a rock but lack linkage to reservoir quality. We here propose an approach for carbonate diagenetic characterization that, in addition to traditional documentation of the paragenetic sequence of cements and pore types, also 1) distills the multifaceted paragenesis into the event(s) that most impacted present-day reservoir quality (Key Paragenetic Step, KPS); 2) graphically depicts the starting point, diagenetic path, and end-product for a particular rock (Paragenogram); and 3) links to the distribution of reservoir quality (flow units) through integration of diagenetic profiles, cumulative-thickness plots, depositional facies, and sequence stratigraphy. To demonstrate this approach, we present examples from carbonate margin and slope facies of the Paleozoic Tengiz field in the Republic of Kazakhstan, where a complex diagenetic history heavily impacted matrix reservoir quality and non-matrix flow characteristics. The dataset consists of 16 cores with thin sections that sample margin grainstone/boundstone-, upper slope boundstone-, middle slope breccia/grainstone-, and lower slope grainstone/mudstone facies assemblages. Using our new approach, we developed a framework that ties diagenetic styles to resulting rock types and improves the linkages between depositional facies, diagenetic overprints, volumetrically significant pore families, and the origins and distribution of enhanced matrix reservoir quality. For example, this work underscored the importance of burial dissolution and its link to improved matrix porosity, permeability, and flow behavior. These findings provide geological context to better understand MICP-derived pore throat data, porosity-permeability distributions, and vertical flow behavior along the borehole, as well as valuable input for log-based Petrophysical Rock Typing. Panel_14761 Panel_14761 4:05 PM 4:25 PM

This abstract is submitted to the session in celebration of the career of Paul “Mitch” Harris. Mitch has taught me that to understand carbonates, you need to investigate all aspects of its depositional and diagenetic history by using core, well logs, seismic interpretation, biostratigraphy, geochemistry, petrography, outcrop analogs and anything else that you can. This project is my attempt to apply his teachings in order to understand the complex reservoir. Significant oil and gas discoveries in the Topkhana and Kurdamir blocks of southeast Kurdistan are primarily contained within the Oligocene Kirkuk group. This group is regionally composed of middle ramp foraminiferal and red algae grainstones as well as coral boundstones/rudstones that likely form small bioherms. Reservoir quality is highly dependent on both the original depositional facies as well as the overprint of dolomitization. Predicting the spatial distribution of the best reservoir quality is challenging. Earlier studies (Hsieh et al., 2013) suggest that the best reservoir rock quality occurs where there is intense dolomitization along with dissolution of the foraminiferal tests. Original intergranular porosity was often occluded by marine cement and thus, non-dolomitized grainstones were considered poorer quality and not the primary target. Based on Sr-isotope geochemistry, dolomitization was shown to occur primarily in the earliest Miocene. This suggested a “top down” dolomitization of the Kirkuk Group where the dolomite geobody would be located beneath the dolomitizing fluid body. Early interpretation of the 3D seismic data supported this hypothesis. However, recently collected cores provided not only a down-dip limit to the dolomitization front, but also added a twist in the reservoir quality story. Dolomitization only improved reservoir quality if the process was complete while partially dolomitized rocks were in fact poorer quality than non-dolomitized rocks. Additionally, coral boundstone and rudstones that seem to preserve the depositional porosity have similar flow properties as the best dolomitized rock. The spatial distribution of the best reservoir quality is therefore a combination of where there is thorough dolomitization as well as where original depositional porosity and permeability is preserved. Isotopic analyses of the new core samples may help to refine the paragenesis and provide a new framework for interpretation of the 3D seismic data. This abstract is submitted to the session in celebration of the career of Paul “Mitch” Harris. Mitch has taught me that to understand carbonates, you need to investigate all aspects of its depositional and diagenetic history by using core, well logs, seismic interpretation, biostratigraphy, geochemistry, petrography, outcrop analogs and anything else that you can. This project is my attempt to apply his teachings in order to understand the complex reservoir. Significant oil and gas discoveries in the Topkhana and Kurdamir blocks of southeast Kurdistan are primarily contained within the Oligocene Kirkuk group. This group is regionally composed of middle ramp foraminiferal and red algae grainstones as well as coral boundstones/rudstones that likely form small bioherms. Reservoir quality is highly dependent on both the original depositional facies as well as the overprint of dolomitization. Predicting the spatial distribution of the best reservoir quality is challenging. Earlier studies (Hsieh et al., 2013) suggest that the best reservoir rock quality occurs where there is intense dolomitization along with dissolution of the foraminiferal tests. Original intergranular porosity was often occluded by marine cement and thus, non-dolomitized grainstones were considered poorer quality and not the primary target. Based on Sr-isotope geochemistry, dolomitization was shown to occur primarily in the earliest Miocene. This suggested a “top down” dolomitization of the Kirkuk Group where the dolomite geobody would be located beneath the dolomitizing fluid body. Early interpretation of the 3D seismic data supported this hypothesis. However, recently collected cores provided not only a down-dip limit to the dolomitization front, but also added a twist in the reservoir quality story. Dolomitization only improved reservoir quality if the process was complete while partially dolomitized rocks were in fact poorer quality than non-dolomitized rocks. Additionally, coral boundstone and rudstones that seem to preserve the depositional porosity have similar flow properties as the best dolomitized rock. The spatial distribution of the best reservoir quality is therefore a combination of where there is thorough dolomitization as well as where original depositional porosity and permeability is preserved. Isotopic analyses of the new core samples may help to refine the paragenesis and provide a new framework for interpretation of the 3D seismic data. Panel_14765 Panel_14765 4:25 PM 4:45 PM

The high-energy platform margin in the Exumas Islands portion of Great Bahama Bank is dominated by a tidal delta depositional motif, typified by islands (Pleistocene or Holocene) bounding open circulating tidal channels within which vigorous tidal flow leads to the formation of flood and ebb tidal lobes formed of ooid and other types of carbonate sands. As shown by the robust example of this motif associated with the tidal channel between Shroud and Hawksbill Cays, significant amounts of sediment form fully aggraded flood and ebb lobes and adjacent sand flats, and are reworked from the ebb tidal lobe by longshore currents and storms to nourish adjacent beaches and form back-beach sand ridges that quickly become cemented by meteoric cements. Isolated Early Holocene (~5,000 years old) eolianites on several islands in the Exumas, e.g. Gaulin Cay, Bitter Guana Cay, Cambridge Cay, O’Brien’s Cay, and Warderick Wells Cay, are problematic, in that these significant relict deposits of ooid and peloid sands with large-scale foreset bedding clearly indicating sediment transport onto the platform are challenging to explain from the standpoint of the source of the carbonate sand. Age-related, coeval facies are lacking, and laterally adjacent shorelines generally lack appreciable Holocene sediment and commonly show signs of erosion and coastline retreat. We propose these eolianites are the result of ebb tidal lobe cannibalization by longshore currents and storms, and their apparent non-equilibrium state with the modern seaward coastline strongly suggests a major change in depositional conditions between time of deposition of the eolianites and present-day. It is likely that tidal delta lobe development occurred in these areas a few thousand years ago during a lower position of sea level when more vigorous tidal currents were concentrated in channels formed in deeper Pleistocene lows. Present sea level has resulted in less vigorous tidal currents in these areas and cannibalization through erosion (longshore currents and storms) of the ebb tidal delta lobe, beach sands, and the seaward portions of the eolianites themselves. The resultant, significant eolianite deposits at these localities are difficult to understand in the absence of their associated early Holocene facies belts, and would pose a very challenging dilemma to explain them in any ancient scenario. Associated facies are missing entirely or are severely truncated. The high-energy platform margin in the Exumas Islands portion of Great Bahama Bank is dominated by a tidal delta depositional motif, typified by islands (Pleistocene or Holocene) bounding open circulating tidal channels within which vigorous tidal flow leads to the formation of flood and ebb tidal lobes formed of ooid and other types of carbonate sands. As shown by the robust example of this motif associated with the tidal channel between Shroud and Hawksbill Cays, significant amounts of sediment form fully aggraded flood and ebb lobes and adjacent sand flats, and are reworked from the ebb tidal lobe by longshore currents and storms to nourish adjacent beaches and form back-beach sand ridges that quickly become cemented by meteoric cements. Isolated Early Holocene (~5,000 years old) eolianites on several islands in the Exumas, e.g. Gaulin Cay, Bitter Guana Cay, Cambridge Cay, O’Brien’s Cay, and Warderick Wells Cay, are problematic, in that these significant relict deposits of ooid and peloid sands with large-scale foreset bedding clearly indicating sediment transport onto the platform are challenging to explain from the standpoint of the source of the carbonate sand. Age-related, coeval facies are lacking, and laterally adjacent shorelines generally lack appreciable Holocene sediment and commonly show signs of erosion and coastline retreat. We propose these eolianites are the result of ebb tidal lobe cannibalization by longshore currents and storms, and their apparent non-equilibrium state with the modern seaward coastline strongly suggests a major change in depositional conditions between time of deposition of the eolianites and present-day. It is likely that tidal delta lobe development occurred in these areas a few thousand years ago during a lower position of sea level when more vigorous tidal currents were concentrated in channels formed in deeper Pleistocene lows. Present sea level has resulted in less vigorous tidal currents in these areas and cannibalization through erosion (longshore currents and storms) of the ebb tidal delta lobe, beach sands, and the seaward portions of the eolianites themselves. The resultant, significant eolianite deposits at these localities are difficult to understand in the absence of their associated early Holocene facies belts, and would pose a very challenging dilemma to explain them in any ancient scenario. Associated facies are missing entirely or are severely truncated. Panel_14762 Panel_14762 4:45 PM 5:05 PM

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Panel_15767 Panel_15767 1:15 PM 12:00 AM

The Cretaceous pre-salt lacustrine carbonates in the Santos Basin, offshore Brazil, are as geologically enigmatic as they are economically valuable. Much debate has centered lately on the extent to which microbes may play a role in their genesis. In marine carbonates, biotic and abiotic calcites can be distinguished based on their isotopic and elemental compositions. In this study, we applied these geochemical tests to thin sections and bulk core samples from well BM-S-22 Guarani-1ST (3-ESSO-004-SPS). Modern calcite-producing taxa often show positive linear covariance in carbon and oxygen isotope compositions. These trends are anchored on the most positive end at abiotic carbonate compositions and extend to more negative values in carbonates precipitated faster. The Guarani samples analyzed in this study show less variation in carbon and oxygen isotope values than many modern calcifiers (like echinoderms, corals, algae), though the range is somewhat consistent with others (like foraminifera). Modern calcite-producing taxa show enrichment in Sr over modern calcite cements as shown on a plot of Mg/Ca vs Sr/Ca. The Guarani samples show this same linear covariance between Mg/Ca and Sr/Ca as well as Sr enrichment, suggesting a biotic influence on their precipitation. These isotopic and elemental data along with scanning electron microscope images showing fossilized microbes seem to be undeniable evidence that biological processes played at least some role in the origin of Brazilian pre-salt lacustrine carbonates. The Cretaceous pre-salt lacustrine carbonates in the Santos Basin, offshore Brazil, are as geologically enigmatic as they are economically valuable. Much debate has centered lately on the extent to which microbes may play a role in their genesis. In marine carbonates, biotic and abiotic calcites can be distinguished based on their isotopic and elemental compositions. In this study, we applied these geochemical tests to thin sections and bulk core samples from well BM-S-22 Guarani-1ST (3-ESSO-004-SPS). Modern calcite-producing taxa often show positive linear covariance in carbon and oxygen isotope compositions. These trends are anchored on the most positive end at abiotic carbonate compositions and extend to more negative values in carbonates precipitated faster. The Guarani samples analyzed in this study show less variation in carbon and oxygen isotope values than many modern calcifiers (like echinoderms, corals, algae), though the range is somewhat consistent with others (like foraminifera). Modern calcite-producing taxa show enrichment in Sr over modern calcite cements as shown on a plot of Mg/Ca vs Sr/Ca. The Guarani samples show this same linear covariance between Mg/Ca and Sr/Ca as well as Sr enrichment, suggesting a biotic influence on their precipitation. These isotopic and elemental data along with scanning electron microscope images showing fossilized microbes seem to be undeniable evidence that biological processes played at least some role in the origin of Brazilian pre-salt lacustrine carbonates. Panel_15106 Panel_15106 1:20 PM 1:40 PM

2-D and 3-D seismic data and multibeam bathymetry provide new clues to fluid-migration pathways and for the first time evidence for potential long-term seafloor gas expulsion on the SE carbonate Florida Platform. On the Miami Terrace, a seafloor collapse structure is underlain by and in close proximity to paleo-pockmarks, a paleo-collapse structure, and paleo-slumps. The bathymetry of the seafloor collapse structure is funnel-shaped, and about 460-m long and 230-m wide along the top. It truncates mainly late Pliocene to Pleistocene strata and tapers downward to form a bottom slightly within Paleogene carbonate strata delineated at the top by a regional erosional unconformity. Calculated gas-chimney probability meta-attribute analysis suggests the presence of a gas chimney below the seafloor collapse structure. An observational report of the seafloor-depression walls indicates they are stratal outcroppings overlain by a 1-m veneer of soft sub-bottom sediment. In addition, a lower feeder pipe or ‘ring’ faults are suggested by the bathymetry data. These findings may rule out an origin related to a gas blowout and could indicate submarine karstic dissolution linked to fluid expulsion. The paleo-pockmarks occur below and to the east of the sinkhole and above the erosional unconformity, constraining the commencement of seafloor fluid-expulsion activity to probably the late Pliocene. Regional mapping and attribute analyses suggest subsurface migration of gas and fluids upward through a system of faults in Paleogene carbonate rocks and eastward stratiform migration up the western flank of an anticline. Attribute analysis also suggests that gas and fluids vent upward through isolated chimneys possibly focused along fractures on the anticlinal flank. Additionally, numerous buried vertical cone-shaped (apex upward) collapse structures are present beneath southeastern peninsular Florida and adjacent inner continental shelf. One of these structures is about 2.3 km high. The structures may have formed by collapse of paleocave systems and protracted, staged, vertical pathway production and fluid migration along faults, fractures, and karstic breccias. Seismic and multibeam data support a model of stair-stepping fluid migration within the carbonate strata of the Florida Platform, with lateral movement along high-permeablity stratiform pathways punctuated by vertical flow focused along karst-collapse structures, and faults and fractures of tectonic origin. 2-D and 3-D seismic data and multibeam bathymetry provide new clues to fluid-migration pathways and for the first time evidence for potential long-term seafloor gas expulsion on the SE carbonate Florida Platform. On the Miami Terrace, a seafloor collapse structure is underlain by and in close proximity to paleo-pockmarks, a paleo-collapse structure, and paleo-slumps. The bathymetry of the seafloor collapse structure is funnel-shaped, and about 460-m long and 230-m wide along the top. It truncates mainly late Pliocene to Pleistocene strata and tapers downward to form a bottom slightly within Paleogene carbonate strata delineated at the top by a regional erosional unconformity. Calculated gas-chimney probability meta-attribute analysis suggests the presence of a gas chimney below the seafloor collapse structure. An observational report of the seafloor-depression walls indicates they are stratal outcroppings overlain by a 1-m veneer of soft sub-bottom sediment. In addition, a lower feeder pipe or ‘ring’ faults are suggested by the bathymetry data. These findings may rule out an origin related to a gas blowout and could indicate submarine karstic dissolution linked to fluid expulsion. The paleo-pockmarks occur below and to the east of the sinkhole and above the erosional unconformity, constraining the commencement of seafloor fluid-expulsion activity to probably the late Pliocene. Regional mapping and attribute analyses suggest subsurface migration of gas and fluids upward through a system of faults in Paleogene carbonate rocks and eastward stratiform migration up the western flank of an anticline. Attribute analysis also suggests that gas and fluids vent upward through isolated chimneys possibly focused along fractures on the anticlinal flank. Additionally, numerous buried vertical cone-shaped (apex upward) collapse structures are present beneath southeastern peninsular Florida and adjacent inner continental shelf. One of these structures is about 2.3 km high. The structures may have formed by collapse of paleocave systems and protracted, staged, vertical pathway production and fluid migration along faults, fractures, and karstic breccias. Seismic and multibeam data support a model of stair-stepping fluid migration within the carbonate strata of the Florida Platform, with lateral movement along high-permeablity stratiform pathways punctuated by vertical flow focused along karst-collapse structures, and faults and fractures of tectonic origin. Panel_15111 Panel_15111 1:40 PM 2:00 PM

The time-equivalent, landward deposits of the Famennian Palliser carbonate platform preserved within the Williston basin have been inaccessible until recent economic interest in the Three Forks Formation. A regional database of polished drill core slabs and petrographic thin sections allowed for detailed analysis of texture, sedimentary structures, ichnological and diagenetic features. XRD and Qemscan mineralogy data were compiled from a variety of cores around the basin. The Three Forks mixed carbonate and siliciclastic intrashelf mudstones facies associations (FA) include: 1) schizohaline storm-dominated shallow shelf, 2) arid shallow shelf and 3) mudflats. FA1 consists of the following lithofacies: (1) distorted claystones that contain moderate abundance of mobile feeding traces and syneresis cracks; (2) laminated mudstones; (3) dolomudstones that include the previous features plus escape burrows, and opportunistic suspension feeding colonies. These facies demonstrate scouring, high depositional rate, storm, and wave features. Additionally, (4) syndepositional deformation through dewatering, evaporite precipitation and dissolution and bioturbation is interpreted to produce brecciated to distorted mudstones; and (5) thin bedded quartz sandstones represent preserved and unmixed fluvial floods into the shallow basin. Arid shallow shelf (FA2) deposits consist of mosaic anhydrites which imply periods of restriction and evaporation at a basinal scale. Mudflat (FA 3) facies include (1) rarely preserved meteorological tide deposited laminated mudstones, and (2) abundantly preserved matrix-supported breccias to (3) massive or intraclastic mudstones. These deposits represent a spectrum of strength and influence of mudflat storm surge that locally transports siltstone clasts derived from the previous facies association. Massive mudstones also commonly have syndepositional anhydrite nodules when associated with the arid shallow shelf system. Storm-generated deposits are preferentially preserved over fairweather deposits. Variable storm strength and resultant geomorphology can result in high vertical facies variability. Regional changes in the stratigraphic section allude to a climatic shift from arid to seasonal in addition to influences from tectonics and sea level. The time-equivalent, landward deposits of the Famennian Palliser carbonate platform preserved within the Williston basin have been inaccessible until recent economic interest in the Three Forks Formation. A regional database of polished drill core slabs and petrographic thin sections allowed for detailed analysis of texture, sedimentary structures, ichnological and diagenetic features. XRD and Qemscan mineralogy data were compiled from a variety of cores around the basin. The Three Forks mixed carbonate and siliciclastic intrashelf mudstones facies associations (FA) include: 1) schizohaline storm-dominated shallow shelf, 2) arid shallow shelf and 3) mudflats. FA1 consists of the following lithofacies: (1) distorted claystones that contain moderate abundance of mobile feeding traces and syneresis cracks; (2) laminated mudstones; (3) dolomudstones that include the previous features plus escape burrows, and opportunistic suspension feeding colonies. These facies demonstrate scouring, high depositional rate, storm, and wave features. Additionally, (4) syndepositional deformation through dewatering, evaporite precipitation and dissolution and bioturbation is interpreted to produce brecciated to distorted mudstones; and (5) thin bedded quartz sandstones represent preserved and unmixed fluvial floods into the shallow basin. Arid shallow shelf (FA2) deposits consist of mosaic anhydrites which imply periods of restriction and evaporation at a basinal scale. Mudflat (FA 3) facies include (1) rarely preserved meteorological tide deposited laminated mudstones, and (2) abundantly preserved matrix-supported breccias to (3) massive or intraclastic mudstones. These deposits represent a spectrum of strength and influence of mudflat storm surge that locally transports siltstone clasts derived from the previous facies association. Massive mudstones also commonly have syndepositional anhydrite nodules when associated with the arid shallow shelf system. Storm-generated deposits are preferentially preserved over fairweather deposits. Variable storm strength and resultant geomorphology can result in high vertical facies variability. Regional changes in the stratigraphic section allude to a climatic shift from arid to seasonal in addition to influences from tectonics and sea level. Panel_15109 Panel_15109 2:00 PM 2:20 PM

Many studies have described the lithologic and facies variations in selected areas of the Eagle Ford Shale but a comprehensive regional investigation linking productivity to facies, lithology, organic matter and water saturation variations has not been presented to date. The Upper Cretaceous Eagle Ford Shale in South Texas is an organic-rich, calcareous mudrock deposited during a second-order transgression of global sea level on a carbonate-dominated shelf updip from the Sligo and Edwards reef margins. Lithology and organic-matter deposition was controlled by fluvial input from the Woodbine Delta in the northeast, upwelling along the Cretaceous shelf edge, and volcanic and clastic input from distant Ouachita and Laramide events in the southwest. Global organic anoxic event (OAE2) contributed to preservation of this organic-rich source rock. These paleogeographic and tectonic elements controlled variations of lithology, amount and distribution of organic matter, and facies that have a profound impact on production quality and production forecasts. A database of wireline logs, total organic content (TOC) calculated from wire line logs (delta log R method), water saturation, lithology, porosity, and thickness of the Lower Eagle Ford was created. Components of the database were used as variables in krieging and multivariate statistical analyses evaluating the impact of these variables on production. For example, TOC and water saturation show an inverse relationship whereas TOC and porosity correlate positively. High productivity zones correlate positively to higher porosity and TOC areas. This method of evaluation not only serves as a tool to predict geologic drivers of production and productivity across the field but also takes the geologic heterogeneity across the Eagle Ford play into account. Many studies have described the lithologic and facies variations in selected areas of the Eagle Ford Shale but a comprehensive regional investigation linking productivity to facies, lithology, organic matter and water saturation variations has not been presented to date. The Upper Cretaceous Eagle Ford Shale in South Texas is an organic-rich, calcareous mudrock deposited during a second-order transgression of global sea level on a carbonate-dominated shelf updip from the Sligo and Edwards reef margins. Lithology and organic-matter deposition was controlled by fluvial input from the Woodbine Delta in the northeast, upwelling along the Cretaceous shelf edge, and volcanic and clastic input from distant Ouachita and Laramide events in the southwest. Global organic anoxic event (OAE2) contributed to preservation of this organic-rich source rock. These paleogeographic and tectonic elements controlled variations of lithology, amount and distribution of organic matter, and facies that have a profound impact on production quality and production forecasts. A database of wireline logs, total organic content (TOC) calculated from wire line logs (delta log R method), water saturation, lithology, porosity, and thickness of the Lower Eagle Ford was created. Components of the database were used as variables in krieging and multivariate statistical analyses evaluating the impact of these variables on production. For example, TOC and water saturation show an inverse relationship whereas TOC and porosity correlate positively. High productivity zones correlate positively to higher porosity and TOC areas. This method of evaluation not only serves as a tool to predict geologic drivers of production and productivity across the field but also takes the geologic heterogeneity across the Eagle Ford play into account. Panel_14967 Panel_14967 2:20 PM 2:40 PM

Panel_15799 Panel_15799 2:40 PM 12:00 AM

The middle Bakken reservoir interval consists of six distinct facies, namely facies A-F. Facies D is the coarsest-grained, highest-energy facies in the entire Bakken Formation. Porosity varies between 1-8%. Lithologically, Facies D varies from very fine- to medium-grained calcite-cemented, quartz-rich sandstone, to ooid-rich grainstone with abundant fossil fragments. Cycles of increasing calcite and decreasing quartz and dolomite, in conjunction with massive zones alternating with zones of high-angle cross-stratification, gives Facies D a banded appearance. The Facies D is discontinuous within the Williston Basin and reaches a maximum thickness of around 5 m in North Dakota. All these features of Facies D highlight the complexity of this mixed siliciclastic-carbonate depositional setting. This study is focused on developing a depositional model for the mixed siliciclastic-carbonate system of Facies D, which will aid in improved middle Bakken reservoir characterization and proper planning of well completions designs . Detailed core descriptions, petrographic studies, log correlations, and subsurface mapping suggest that Facies D was deposited in a middle to lower shoreface environment in a homoclinal ramp setting. Presence of oolitic grainstones and a restricted faunal assemblage indicate that it was deposited in a saline basin under arid conditions. The principal carbonate factory existed in the southern part of the basin, while the siliciclastic source was from the north. Thickened intervals of Facies D correspond to building up of carbonate shoals that are cross cut by intervening channels, similar to the ebb delta ooid shoals of eastern Abu Dhabi. Tidal currents and storm-generated flows within these channels distributed both siliciclastic and carbonate sediments across the basin. Seasonal variations in wind direction, as seen in the modern day Sunda Shelf in South China Sea, influenced current intensity within the channels. This resulted in cyclic deposition of alternating bands of oolitic grainstone and quartz-rich sandstone. Fast Fourier Transform analysis is applied to understand this complex interaction between tidal influence and seasonal variations in a mixed siliciclastic-carbonate depositional setting. The middle Bakken reservoir interval consists of six distinct facies, namely facies A-F. Facies D is the coarsest-grained, highest-energy facies in the entire Bakken Formation. Porosity varies between 1-8%. Lithologically, Facies D varies from very fine- to medium-grained calcite-cemented, quartz-rich sandstone, to ooid-rich grainstone with abundant fossil fragments. Cycles of increasing calcite and decreasing quartz and dolomite, in conjunction with massive zones alternating with zones of high-angle cross-stratification, gives Facies D a banded appearance. The Facies D is discontinuous within the Williston Basin and reaches a maximum thickness of around 5 m in North Dakota. All these features of Facies D highlight the complexity of this mixed siliciclastic-carbonate depositional setting. This study is focused on developing a depositional model for the mixed siliciclastic-carbonate system of Facies D, which will aid in improved middle Bakken reservoir characterization and proper planning of well completions designs . Detailed core descriptions, petrographic studies, log correlations, and subsurface mapping suggest that Facies D was deposited in a middle to lower shoreface environment in a homoclinal ramp setting. Presence of oolitic grainstones and a restricted faunal assemblage indicate that it was deposited in a saline basin under arid conditions. The principal carbonate factory existed in the southern part of the basin, while the siliciclastic source was from the north. Thickened intervals of Facies D correspond to building up of carbonate shoals that are cross cut by intervening channels, similar to the ebb delta ooid shoals of eastern Abu Dhabi. Tidal currents and storm-generated flows within these channels distributed both siliciclastic and carbonate sediments across the basin. Seasonal variations in wind direction, as seen in the modern day Sunda Shelf in South China Sea, influenced current intensity within the channels. This resulted in cyclic deposition of alternating bands of oolitic grainstone and quartz-rich sandstone. Fast Fourier Transform analysis is applied to understand this complex interaction between tidal influence and seasonal variations in a mixed siliciclastic-carbonate depositional setting. Panel_15104 Panel_15104 3:25 PM 3:45 PM

Exploitation of hydrocarbons from strata with evaporite paleokarst development can be challenging due to tremendous permeability variability as a result of disrupted bedding, irregular pore types, allochthonous and autochthonous sediment fills and the development of persistent fractures throughout. Porosity networks and permeability barriers linked to evaporite paleokarst are critical elements of major hydrocarbon accumulations such as the Madison Formation of the Bighorn Basin. The extensive suprastratal deformation can create substantial permeability heterogeneity, directly juxtaposed to the dissolution zones themselves that commonly form low flow baffles or barriers. Despite these important and widespread characteristics, no systematic treatment of this style of carbonate reservoir heterogeneity exists and as a result of the “vanished” nature of the key controlling lithofacies, these systems are commonly controversial and poorly understood. The Upper Mississippian Madison Group offers a superb, if not spectacular, exposure of laterally continuous evaporite paleokarst zones. Many studies have described solution enhanced zones within the Madison. The focus of this study is the reservoir heterogeneity scale issues associated with this evaporite removal system. Thus we build upon the impressive regional syntheses available for this Mississippian platform and treat a limited number of key localities in Wyoming and Montana in some detail. Observations from these localities have led to a list of criteria for recognition of evaporite paleokarst that, while based on the Madison, are also present in other evaporite paleokarst systems. We interpret the timing of the paleokarst system, including the two distinct styles of paleokarst: end Madison subaerial exposure and the intrastratal solution collapse. We relate this to overall paleogeography and tectonic elements within the late Mississippian. Finally, we highlight important observations regarding reservoir architectural elements that have significant implications for hydrocarbon development, especially in the form of highly fractured strata above the evaporite removal zone. Exploitation of hydrocarbons from strata with evaporite paleokarst development can be challenging due to tremendous permeability variability as a result of disrupted bedding, irregular pore types, allochthonous and autochthonous sediment fills and the development of persistent fractures throughout. Porosity networks and permeability barriers linked to evaporite paleokarst are critical elements of major hydrocarbon accumulations such as the Madison Formation of the Bighorn Basin. The extensive suprastratal deformation can create substantial permeability heterogeneity, directly juxtaposed to the dissolution zones themselves that commonly form low flow baffles or barriers. Despite these important and widespread characteristics, no systematic treatment of this style of carbonate reservoir heterogeneity exists and as a result of the “vanished” nature of the key controlling lithofacies, these systems are commonly controversial and poorly understood. The Upper Mississippian Madison Group offers a superb, if not spectacular, exposure of laterally continuous evaporite paleokarst zones. Many studies have described solution enhanced zones within the Madison. The focus of this study is the reservoir heterogeneity scale issues associated with this evaporite removal system. Thus we build upon the impressive regional syntheses available for this Mississippian platform and treat a limited number of key localities in Wyoming and Montana in some detail. Observations from these localities have led to a list of criteria for recognition of evaporite paleokarst that, while based on the Madison, are also present in other evaporite paleokarst systems. We interpret the timing of the paleokarst system, including the two distinct styles of paleokarst: end Madison subaerial exposure and the intrastratal solution collapse. We relate this to overall paleogeography and tectonic elements within the late Mississippian. Finally, we highlight important observations regarding reservoir architectural elements that have significant implications for hydrocarbon development, especially in the form of highly fractured strata above the evaporite removal zone. Panel_15105 Panel_15105 3:45 PM 4:05 PM

Recent hydrocarbon exploration targeting the unconventional Niobrara Formation has renewed interest in Late Cretaceous mudstones of the Western Interior. A robust sequence stratigraphic framework of this mixed siliciclastic-carbonate system from Cenomanian – Campanian time will have the potential to improve exploration strategies and provide new insight into the stratigraphic relationships across two third order sequences. This study builds an integrated sequence stratigraphic framework based on sedimentology, high-resolution carbon and oxygen stable isotope chemostratigraphy, elemental chemostratigraphy, and borehole image analysis of the Greenhorn, Carlile, and Niobrara Formations (GCN) in the Denver Basin, CO, U.S.A. Sedimentological analysis was conducted using core, thin sections, and QEMSCAN to document the primary facies of the GCN. High-resolution (6-inch to 3-foot sample spacing) carbon and oxygen stable isotope measurements were taken from eight cores in the Denver Basin, CO, U.S.A. Previous studies linking carbon isotope chemostratigraphy to biostratigraphy and radiometric age dating provide a robust foundation from which carbon isotope chemostratigraphy can be used as a chronostratigraphic tool in the Western Interior. Borehole image analysis was conducted using an automated bed thickness measurement technique. Results show new high-resolution carbon isotope chemostratigraphic correlations across the Denver Basin, CO and their relationship to systems tracts. Oxygen isotope chemostratigraphy shows variable absolute values, but consistent trends among the eight cores. Chronostratigraphic application of carbon isotope chemostratigraphy shows that lithostratigraphy is consistent with chronostratigraphy in the Denver Basin, CO. Carbon isotope chemostratigraphy is observed to make gradual excursions across complete sections. Excursions that are abrupt are evidence of missing section or depositional hiatus. A relationship between carbon isotope chemostratigraphy and systems tracts can also be seen. Recent hydrocarbon exploration targeting the unconventional Niobrara Formation has renewed interest in Late Cretaceous mudstones of the Western Interior. A robust sequence stratigraphic framework of this mixed siliciclastic-carbonate system from Cenomanian – Campanian time will have the potential to improve exploration strategies and provide new insight into the stratigraphic relationships across two third order sequences. This study builds an integrated sequence stratigraphic framework based on sedimentology, high-resolution carbon and oxygen stable isotope chemostratigraphy, elemental chemostratigraphy, and borehole image analysis of the Greenhorn, Carlile, and Niobrara Formations (GCN) in the Denver Basin, CO, U.S.A. Sedimentological analysis was conducted using core, thin sections, and QEMSCAN to document the primary facies of the GCN. High-resolution (6-inch to 3-foot sample spacing) carbon and oxygen stable isotope measurements were taken from eight cores in the Denver Basin, CO, U.S.A. Previous studies linking carbon isotope chemostratigraphy to biostratigraphy and radiometric age dating provide a robust foundation from which carbon isotope chemostratigraphy can be used as a chronostratigraphic tool in the Western Interior. Borehole image analysis was conducted using an automated bed thickness measurement technique. Results show new high-resolution carbon isotope chemostratigraphic correlations across the Denver Basin, CO and their relationship to systems tracts. Oxygen isotope chemostratigraphy shows variable absolute values, but consistent trends among the eight cores. Chronostratigraphic application of carbon isotope chemostratigraphy shows that lithostratigraphy is consistent with chronostratigraphy in the Denver Basin, CO. Carbon isotope chemostratigraphy is observed to make gradual excursions across complete sections. Excursions that are abrupt are evidence of missing section or depositional hiatus. A relationship between carbon isotope chemostratigraphy and systems tracts can also be seen. Panel_15107 Panel_15107 4:05 PM 4:25 PM

Depositional interpretation and sequence stratigraphic analysis of carbonate mudrocks requires numerical analysis and data integration to achieve quantitative, predictive stratigraphic and geochemical models. To demonstrate proof of concept, a depositional and sequence stratigraphic analysis has been done on a basinal interval of the Tuwaiq Mountain and Hanifa formations, Saudi Arabia. Conventional geologic interpretation, automated electrofacies analysis, and geochemical interpretation are integrated using quantitative means. Cluster analysis of well-logs using self-organizing maps and hierarchical clustering allowed for a multiscale electrofacies analysis. This is useful for identifying major lithological surfaces, which commonly correspond to sequence stratigraphic surfaces. Geochemical data was used for depositional environment interpretation, such as sediment provenance, redox, and paleoproductivity conditions. Factor analysis is used to group element data. Redox and paleoproductivity indices were calculated using electrofacies clustering of different elemental groups. Electrofacies analysis shows good correlation with the lithofacies. Five major lithofacies have been identified in the studied interval. The majority of the interval is interpreted to be deposited as gravity flow deposits in an outer ramp setting. Two major sequences have been identified in the Tuwaiq Mountain Formation. The first is composed of the Atash, Hisyan, and Baladiyah (T1) members. The second corresponds to the Maysiyah (T2), and Daddiyah (T3) members. Two major depositional sequences have been identified in the Hanifa Formation corresponding to the Hawtah and Ulayyah members. The uppermost bioturbated packstones of the Ulayyah Member are interpreted to be a lowstand systems tract with subsequent restriction leading to the deposition of anhydrite. In the studied interval, total organic carbon content (TOC) correlates well with suboxic to anoxic intervals that have high paleoproductivity. Complete anoxia is not a prerequisite for organic matter preservation. High TOC intervals are mainly in transgressive systems tracts. Depositional interpretation and sequence stratigraphic analysis of carbonate mudrocks requires numerical analysis and data integration to achieve quantitative, predictive stratigraphic and geochemical models. To demonstrate proof of concept, a depositional and sequence stratigraphic analysis has been done on a basinal interval of the Tuwaiq Mountain and Hanifa formations, Saudi Arabia. Conventional geologic interpretation, automated electrofacies analysis, and geochemical interpretation are integrated using quantitative means. Cluster analysis of well-logs using self-organizing maps and hierarchical clustering allowed for a multiscale electrofacies analysis. This is useful for identifying major lithological surfaces, which commonly correspond to sequence stratigraphic surfaces. Geochemical data was used for depositional environment interpretation, such as sediment provenance, redox, and paleoproductivity conditions. Factor analysis is used to group element data. Redox and paleoproductivity indices were calculated using electrofacies clustering of different elemental groups. Electrofacies analysis shows good correlation with the lithofacies. Five major lithofacies have been identified in the studied interval. The majority of the interval is interpreted to be deposited as gravity flow deposits in an outer ramp setting. Two major sequences have been identified in the Tuwaiq Mountain Formation. The first is composed of the Atash, Hisyan, and Baladiyah (T1) members. The second corresponds to the Maysiyah (T2), and Daddiyah (T3) members. Two major depositional sequences have been identified in the Hanifa Formation corresponding to the Hawtah and Ulayyah members. The uppermost bioturbated packstones of the Ulayyah Member are interpreted to be a lowstand systems tract with subsequent restriction leading to the deposition of anhydrite. In the studied interval, total organic carbon content (TOC) correlates well with suboxic to anoxic intervals that have high paleoproductivity. Complete anoxia is not a prerequisite for organic matter preservation. High TOC intervals are mainly in transgressive systems tracts. Panel_15108 Panel_15108 4:25 PM 4:45 PM

Fractures, both stimulated and natural, are critical to producing unconventional source-rock reservoirs. Open natural fractures commonly enhance production. However, where mineralized these fractures might still have higher permeability than the matrix and also can act as planes of weakness during stimulation. This presentation describes early-formed, mineralized fractures (veins) common to several unconventional reservoirs. These crumpled veins are differentially compacted in the muddy host-rock, indicating an origin during shallow burial. Veins are typically ribbon-like, and can be isolated or in a ‘swarm’. They commonly have mm- to cm-scale kinematic apertures, mm- to at least cm-scale lengths, and mm- to dm-scale heights. Veins can be filled with barite, calcite, dolomite, silica, euhedral to anhedral pyrite, and fragments of the host sediment. These mineralized fractures are akin to ‘molar tooth’ structures (MTS)—synsedimentary veins thought to be restricted to Precambrian shallow subtidal mudstones. MTS have similarly sized, crumpled, ribbon-like morphologies, but can also occur as spherical blebs. They are commonly differentially compacted with host sediment and reworked into lags at the base of storm beds, indicating an origin shallow in the sediment pile. MTS are distinguished by their distinctive fill: uniform carbonate microspar, with minor amounts of pyrite or host-sediment. Many origins have been proposed for MTS, including synaeresis, earthquake or storm wave loading, and gas expansion. Most MTS are best explained as mineralized bubbles and expansion cracks from the decay of organic matter in cohesive, porous muds. A similar origin is likely for veins in Phanerozoic unconventional reservoirs, known to be porous, cohesive, and rich in organic carbon. The restriction of MTS to Precambrian rocks has previously been attributed to sediment rheology and pore water geochemistry: MTS required cohesive muds, the absence of bioturbation, and rapid cementation from modified seawater. The occurrence of MTS-like veins in Phanerozoic source rocks extends the range for these unusual sedimentary structures outside of the Precambrian—indicating that similar sediment rheology existed locally. It indicates also that rapid cementation was possible in Phanerozoic sediments, though the cements morphologies differ. Finally, such veins may be an important indicator for primary organic-richness in ancient muddy sediments. Fractures, both stimulated and natural, are critical to producing unconventional source-rock reservoirs. Open natural fractures commonly enhance production. However, where mineralized these fractures might still have higher permeability than the matrix and also can act as planes of weakness during stimulation. This presentation describes early-formed, mineralized fractures (veins) common to several unconventional reservoirs. These crumpled veins are differentially compacted in the muddy host-rock, indicating an origin during shallow burial. Veins are typically ribbon-like, and can be isolated or in a ‘swarm’. They commonly have mm- to cm-scale kinematic apertures, mm- to at least cm-scale lengths, and mm- to dm-scale heights. Veins can be filled with barite, calcite, dolomite, silica, euhedral to anhedral pyrite, and fragments of the host sediment. These mineralized fractures are akin to ‘molar tooth’ structures (MTS)—synsedimentary veins thought to be restricted to Precambrian shallow subtidal mudstones. MTS have similarly sized, crumpled, ribbon-like morphologies, but can also occur as spherical blebs. They are commonly differentially compacted with host sediment and reworked into lags at the base of storm beds, indicating an origin shallow in the sediment pile. MTS are distinguished by their distinctive fill: uniform carbonate microspar, with minor amounts of pyrite or host-sediment. Many origins have been proposed for MTS, including synaeresis, earthquake or storm wave loading, and gas expansion. Most MTS are best explained as mineralized bubbles and expansion cracks from the decay of organic matter in cohesive, porous muds. A similar origin is likely for veins in Phanerozoic unconventional reservoirs, known to be porous, cohesive, and rich in organic carbon. The restriction of MTS to Precambrian rocks has previously been attributed to sediment rheology and pore water geochemistry: MTS required cohesive muds, the absence of bioturbation, and rapid cementation from modified seawater. The occurrence of MTS-like veins in Phanerozoic source rocks extends the range for these unusual sedimentary structures outside of the Precambrian—indicating that similar sediment rheology existed locally. It indicates also that rapid cementation was possible in Phanerozoic sediments, though the cements morphologies differ. Finally, such veins may be an important indicator for primary organic-richness in ancient muddy sediments. Panel_15110 Panel_15110 4:45 PM 5:05 PM

Channels are conduits through which fluids, sediment (suspended and bed-load) and dissolved loads are transported across the Earth surface. Their general geomorphologic expression is comparable similar in terrestrial, submarine and extraterrestrial environments; however, formative sedimentary processes can be fundamentally different. For example, sinuosity and aspect ratio tend to be similar; however, submarine channels tend to be larger than fluvial channels and the stratigraphic records of fluvial and submarine channel deposits can be different. A key research challenge is the link between the geomorphic expression and stratigraphic record of channels. Rivers are more accessible to direct monitoring compared to submarine channels and the link between fluvial geomorphology and stratigraphy is better understood. In the case of submarine channels, we commonly rely on the stratigraphic record to inform insights about formative processes and evolution.

Channels are conduits through which fluids, sediment (suspended and bed-load) and dissolved loads are transported across the Earth surface. Their general geomorphologic expression is comparable similar in terrestrial, submarine and extraterrestrial environments; however, formative sedimentary processes can be fundamentally different. For example, sinuosity and aspect ratio tend to be similar; however, submarine channels tend to be larger than fluvial channels and the stratigraphic records of fluvial and submarine channel deposits can be different. A key research challenge is the link between the geomorphic expression and stratigraphic record of channels. Rivers are more accessible to direct monitoring compared to submarine channels and the link between fluvial geomorphology and stratigraphy is better understood. In the case of submarine channels, we commonly rely on the stratigraphic record to inform insights about formative processes and evolution.

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Panel_15817 Panel_15817 1:15 PM 12:00 AM

Here we consider the puzzle of long-runout turbidity currents and the channels they create. It is well known, through direct evidence of the flows or from the morphology that they create, that turbidity currents can run out over 1000 km in the ocean. The currents do so without dissipating themselves via the excess entrainment of ambient water. Existing layer-averaged formulations are, however, unable to capture this behavior. Here we use the formalism of a “Turbidity Current with a Roof” to show that the turbidity current partitions itself into two layers. The lower “driving layer” approaches an asymptotic behavior with invariant flow thickness, velocity profile and suspended sediment concentration profile. The upper “rarified layer” continues to entrain ambient water indefinitely, but the concentration in that layer becomes ever more dilute, and the layer ultimately has little interaction with bed morphology. This partition likely allows the driving layer to run out long distances while maintaining coherence, and to follow morphology of its own creation such as leveed subaqueous channels. Here we consider the puzzle of long-runout turbidity currents and the channels they create. It is well known, through direct evidence of the flows or from the morphology that they create, that turbidity currents can run out over 1000 km in the ocean. The currents do so without dissipating themselves via the excess entrainment of ambient water. Existing layer-averaged formulations are, however, unable to capture this behavior. Here we use the formalism of a “Turbidity Current with a Roof” to show that the turbidity current partitions itself into two layers. The lower “driving layer” approaches an asymptotic behavior with invariant flow thickness, velocity profile and suspended sediment concentration profile. The upper “rarified layer” continues to entrain ambient water indefinitely, but the concentration in that layer becomes ever more dilute, and the layer ultimately has little interaction with bed morphology. This partition likely allows the driving layer to run out long distances while maintaining coherence, and to follow morphology of its own creation such as leveed subaqueous channels. Panel_14857 Panel_14857 1:20 PM 1:40 PM

Submarine channel systems are typically described by their current surface morphology and potentially the buried seismic stratigraphy. The stratigraphy presents the net result of accumulation but does not necessary show the evolution of the surface morphology. Active fjord delta channels change fast enough that repetitive surveying can monitor the evolution of the active geomorphic surface including both accretion and erosional events. Mapping of submarine prodeltas and distal channels in fjords in British Columbia over a decade has revealed their evolution over timescales ranging from years to days and as short as a few minutes. Over the shorter time scales, characteristics of the flow within the proximal channels have been directly monitored in a number of ways. Velocity and suspended sediment profiles and vertical and plan view imaging of surge-type turbidity currents have been obtained. Furthermore, the modification of underlying bedforms on the channel floors has been observed directly associated with those flows. The cumulative impact of episodic upslope migration of bedforms has been seen to be one of the major mechanisms by which the channels evolve over time. At the more distal locations, the dominant channel floor morphology appears to be characterized by knickpoints which, although a much longer length scale than the proximal bedforms, also migrate upslope over time. Over a time scale of years, the knickpoint migration appears to be the single largest influence on the temporal evolution of those channels . At the distal termination of the fjord floor channels, depositional lobes have previously been described by others. Using repetitive surveys over timescales of a few years, the cumulative growth of these lobes has now been monitored. This provides the 3D geometry of the intervening lens. Both the underlying surface and the modern surface can be delineated revealing the spatial variation of the thickness of the accumulation. Again, periodic downstream undulations in the thickness of the lens appear to indicate upcurrent migration of this very long wavelength relief. Taken together, the temporal evolution of channels from the proximal delta front to the distal depositional lobes provides a potential analog for the much slower evolution of deep-sea channel systems. Submarine channel systems are typically described by their current surface morphology and potentially the buried seismic stratigraphy. The stratigraphy presents the net result of accumulation but does not necessary show the evolution of the surface morphology. Active fjord delta channels change fast enough that repetitive surveying can monitor the evolution of the active geomorphic surface including both accretion and erosional events. Mapping of submarine prodeltas and distal channels in fjords in British Columbia over a decade has revealed their evolution over timescales ranging from years to days and as short as a few minutes. Over the shorter time scales, characteristics of the flow within the proximal channels have been directly monitored in a number of ways. Velocity and suspended sediment profiles and vertical and plan view imaging of surge-type turbidity currents have been obtained. Furthermore, the modification of underlying bedforms on the channel floors has been observed directly associated with those flows. The cumulative impact of episodic upslope migration of bedforms has been seen to be one of the major mechanisms by which the channels evolve over time. At the more distal locations, the dominant channel floor morphology appears to be characterized by knickpoints which, although a much longer length scale than the proximal bedforms, also migrate upslope over time. Over a time scale of years, the knickpoint migration appears to be the single largest influence on the temporal evolution of those channels . At the distal termination of the fjord floor channels, depositional lobes have previously been described by others. Using repetitive surveys over timescales of a few years, the cumulative growth of these lobes has now been monitored. This provides the 3D geometry of the intervening lens. Both the underlying surface and the modern surface can be delineated revealing the spatial variation of the thickness of the accumulation. Again, periodic downstream undulations in the thickness of the lens appear to indicate upcurrent migration of this very long wavelength relief. Taken together, the temporal evolution of channels from the proximal delta front to the distal depositional lobes provides a potential analog for the much slower evolution of deep-sea channel systems. Panel_14858 Panel_14858 1:40 PM 2:00 PM

Many decades of studies of deposits and seascapes formed by turbidity currents have established that patterns are repeated through time and space, a prominent example being the tendency to form and fill channel conduits. Much more recently, the process-modeling community has made progress in the understanding of the distribution of suspended sediment, velocity, and turbulence in turbidity currents, together shaping the “flow structure”. Thus, now is the time to integrate, and investigate in more detail how the process of sediment erosion, transport, and deposition by turbidity currents is related to observed systematics in the physical products preserved in the geological record. Here, we use results from experimental sandy turbidity current studies and insights from published literature to investigate: (1) The morphodynamic co-evolution of the flow structure and the channel morphology during an elementary cycle. This elementary cycle constitutes three phases: channel establishment, channel maintenance, and channel fill. Understanding of the elementary cycle of channelization can help to establish the organization of fundamental building blocks of stratigraphy, and can be applied in modelling of subsurface occurrences of channel deposits. (2) Determinations of the sediment budget of channels from their morphology, which can be applied to make predictions of sediment volumes stored in correlated bodies down-dip. (3) A comparison between experimental channel shapes and channel-fill deposit metrics obtained from literature, which raises a number of important questions; about the relation between morphological conduits and fill-deposit shape; about the controls on transition from channel formation to channel filling; and about the usefulness of choosing system analogues based on simple channel-fill metric concurrence. Some of these questions need to be addressed before truly predictive application claimed under (1) & (2) is feasible. Many decades of studies of deposits and seascapes formed by turbidity currents have established that patterns are repeated through time and space, a prominent example being the tendency to form and fill channel conduits. Much more recently, the process-modeling community has made progress in the understanding of the distribution of suspended sediment, velocity, and turbulence in turbidity currents, together shaping the “flow structure”. Thus, now is the time to integrate, and investigate in more detail how the process of sediment erosion, transport, and deposition by turbidity currents is related to observed systematics in the physical products preserved in the geological record. Here, we use results from experimental sandy turbidity current studies and insights from published literature to investigate: (1) The morphodynamic co-evolution of the flow structure and the channel morphology during an elementary cycle. This elementary cycle constitutes three phases: channel establishment, channel maintenance, and channel fill. Understanding of the elementary cycle of channelization can help to establish the organization of fundamental building blocks of stratigraphy, and can be applied in modelling of subsurface occurrences of channel deposits. (2) Determinations of the sediment budget of channels from their morphology, which can be applied to make predictions of sediment volumes stored in correlated bodies down-dip. (3) A comparison between experimental channel shapes and channel-fill deposit metrics obtained from literature, which raises a number of important questions; about the relation between morphological conduits and fill-deposit shape; about the controls on transition from channel formation to channel filling; and about the usefulness of choosing system analogues based on simple channel-fill metric concurrence. Some of these questions need to be addressed before truly predictive application claimed under (1) & (2) is feasible. Panel_14860 Panel_14860 2:00 PM 2:20 PM

To gain a better understanding of fundamental submarine channel processes and products, we explore geomorphic and stratigraphic records of deep-sea channelized systems through the lenses of modern Earth surface and latest Quaternary continental margins of the west coast of North America, and outcrops of the Cretaceous Magallanes Basin, Chile. Channelized sedimentary systems offshore of the west coast of North America show a breadth of geomorphology and stratigraphic architecture, including channel reaches of varying sinuosity, levees, terraces within channels, and sediment waves in incipient channels and along thalwegs of well-developed channels. Repeat bathymetric surveys of submarine channels in fjords of British Columbia and the Monterey Canyon underscore the transience of fine-scale detail in channelized geomorphology, and sedimentary processes likely active during channel evolution, such as the frequent, multi-phase bed reworking, local deposition, and bypass of turbidity currents. Submarine channel deposits of the Tres Pasos Formation, Chile, include uniquely preserved thin-bedded and fine-grained channel margin units, the deposits of which drape or lap onto the composite edge of the channelform, as well as scours of diverse scales. These characteristics reveal a complex, multi-phase and multi-scale history of incision and bypass of turbidity currents. The stratigraphic evidence for dynamic sedimentary processes of channel evolution in this system is consistent with observations of submarine channels offshore of the west coast of North America. These geomorphic and stratigraphic records provide evidence of the full channel evolutionary cycle, from inception through protracted maintenance by predominantly bypassing sediment gravity flows, to terminal infill with sediment. The primary function of submarine channels is sediment transfer; the stratigraphic record is biased by the sand-rich products of shorter-lived channel filling and abandonment. Our integrated approach of deciphering channelized sedimentary processes, based on modern and ancient analogs, provides a more complete understanding of fundamental submarine sediment-routing processes, as well as insights into channel connectivity and facies heterogeneity. To gain a better understanding of fundamental submarine channel processes and products, we explore geomorphic and stratigraphic records of deep-sea channelized systems through the lenses of modern Earth surface and latest Quaternary continental margins of the west coast of North America, and outcrops of the Cretaceous Magallanes Basin, Chile. Channelized sedimentary systems offshore of the west coast of North America show a breadth of geomorphology and stratigraphic architecture, including channel reaches of varying sinuosity, levees, terraces within channels, and sediment waves in incipient channels and along thalwegs of well-developed channels. Repeat bathymetric surveys of submarine channels in fjords of British Columbia and the Monterey Canyon underscore the transience of fine-scale detail in channelized geomorphology, and sedimentary processes likely active during channel evolution, such as the frequent, multi-phase bed reworking, local deposition, and bypass of turbidity currents. Submarine channel deposits of the Tres Pasos Formation, Chile, include uniquely preserved thin-bedded and fine-grained channel margin units, the deposits of which drape or lap onto the composite edge of the channelform, as well as scours of diverse scales. These characteristics reveal a complex, multi-phase and multi-scale history of incision and bypass of turbidity currents. The stratigraphic evidence for dynamic sedimentary processes of channel evolution in this system is consistent with observations of submarine channels offshore of the west coast of North America. These geomorphic and stratigraphic records provide evidence of the full channel evolutionary cycle, from inception through protracted maintenance by predominantly bypassing sediment gravity flows, to terminal infill with sediment. The primary function of submarine channels is sediment transfer; the stratigraphic record is biased by the sand-rich products of shorter-lived channel filling and abandonment. Our integrated approach of deciphering channelized sedimentary processes, based on modern and ancient analogs, provides a more complete understanding of fundamental submarine sediment-routing processes, as well as insights into channel connectivity and facies heterogeneity. Panel_14863 Panel_14863 2:20 PM 2:40 PM

Panel_15818 Panel_15818 2:40 PM 12:00 AM

Sedimentary processes and resultant facies in submarine canyons are poorly understood because canyons are bathymetrically complex and sedimentologically heterogeneous environments. Thus it has proven difficult to study submarine canyons using traditional wire-line coring techniques. This study uses a novel vibracoring system deployed using a remotely operated vehicle that enables precise core location (latitude, longitude and altitude above thalweg) and can capture coarse-grained sediments. Whilst previous studies have focused on individual canyons, this study makes use of 127 cores from 22 canyons along a 600 km stretch of the California margin enabling recognition of different canyon types and identification of the processes that control them. Canyons can be divided into two types: coarse-grained canyons and fine-grained canyons. Coarse-grained canyons have a sharply defined thalweg-channel filled with chaotic sands and gravels, episodic movement of these coarse sediments maintains and probably actively erodes the thalweg-channel; finer grained sands and silts drape the canyon walls. Fine-grained canyons have a poorly defined thalweg-channel and are filled with fine-grained sands and silts that anneal preexisting channel topography and drape the canyon walls. Coarse-grained canyons are formed where the canyon head intersects the local littoral cell, whereas fine-grained canyons have heads on the continental shelf. Facies type, grain size and composition (% sand) are strongly constrained by altitude above the thalweg and much less by distance down canyon. Whereas the grain size of fine-grained facies comprising sands and silts fines slightly down canyon, the sands and gravels in the canyon axis show no such fining. This lack of fining may reflect episodic remobilization of material during numerous sediment transport events. Infilling of canyons by frequent small events and flushing by occasional large events has been inferred for many decades. Two of the canyons studied have areas devoid of canyon fill, where bedrock is exposed. High-resolution bathymetry within one of these canyons reveals that scouring of the previous canyon fill, presumably by exceptionally high-energy flow events, has exposed the bedrock. This study reveals the spectrum of processes operating in modern canyons are controlled by the type and volume of sediment available and whether the canyon can tap these supplies, which is strongly dependent on the position of the canyon head. Sedimentary processes and resultant facies in submarine canyons are poorly understood because canyons are bathymetrically complex and sedimentologically heterogeneous environments. Thus it has proven difficult to study submarine canyons using traditional wire-line coring techniques. This study uses a novel vibracoring system deployed using a remotely operated vehicle that enables precise core location (latitude, longitude and altitude above thalweg) and can capture coarse-grained sediments. Whilst previous studies have focused on individual canyons, this study makes use of 127 cores from 22 canyons along a 600 km stretch of the California margin enabling recognition of different canyon types and identification of the processes that control them. Canyons can be divided into two types: coarse-grained canyons and fine-grained canyons. Coarse-grained canyons have a sharply defined thalweg-channel filled with chaotic sands and gravels, episodic movement of these coarse sediments maintains and probably actively erodes the thalweg-channel; finer grained sands and silts drape the canyon walls. Fine-grained canyons have a poorly defined thalweg-channel and are filled with fine-grained sands and silts that anneal preexisting channel topography and drape the canyon walls. Coarse-grained canyons are formed where the canyon head intersects the local littoral cell, whereas fine-grained canyons have heads on the continental shelf. Facies type, grain size and composition (% sand) are strongly constrained by altitude above the thalweg and much less by distance down canyon. Whereas the grain size of fine-grained facies comprising sands and silts fines slightly down canyon, the sands and gravels in the canyon axis show no such fining. This lack of fining may reflect episodic remobilization of material during numerous sediment transport events. Infilling of canyons by frequent small events and flushing by occasional large events has been inferred for many decades. Two of the canyons studied have areas devoid of canyon fill, where bedrock is exposed. High-resolution bathymetry within one of these canyons reveals that scouring of the previous canyon fill, presumably by exceptionally high-energy flow events, has exposed the bedrock. This study reveals the spectrum of processes operating in modern canyons are controlled by the type and volume of sediment available and whether the canyon can tap these supplies, which is strongly dependent on the position of the canyon head. Panel_14864 Panel_14864 3:25 PM 3:45 PM

Submarine channels are common and persistent features in the modern seascape and stratigraphic record, and represent fundamental reservoir architectures in petroleum systems. Utilizing morphological, kinematic, and architectural (stratigraphic) data, this study documents planform and vertical scaling relationships for submarine channels. We also compare these scaling relationships to subaerial channels (i.e., rivers) to illustrate differences and similarities in morphology and architecture. Using modern bathymetric, high-resolution 3D seismic, core/well, and outcrop data, we have developed an extensive database of planform and vertical channel scales and measurement metrics for submarine channels. Multiple scales of channelized features were extracted and analyzed, including: the geomorphic channel form, oxbow-cutoffs, channel trajectory/mobility, and preserved deposit thickness. Geometric statistics resulting from these features were used to derive scaling relationships relevant to reservoir characterization. These scaling relationships are coupled with additional data (e.g., basin type, slope morphology, net-to-gross) to identify and highlight the first order physical controls on channel morphology, kinematics, and resultant architecture. These controls form the basis for a classification of submarine channels that is objective and quantitative. This classification system is process-based and allows for the prediction of scale, architecture, and heterogeneity of submarine channel deposits of all scales. Subaerial and and submarine channels exhibit qualitatively similar morphology, but their stratigraphic record is known to be quite different. Submarine channel scaling relationships use many of the same metrics as those developed for river systems, allowing for the quantification of differences and similarities. These scaling relationships are highly relevant in both exploration and development settings, where they aid in volumetric analysis as well as heterogeneity prediction and reservoir model construction. Submarine channels are common and persistent features in the modern seascape and stratigraphic record, and represent fundamental reservoir architectures in petroleum systems. Utilizing morphological, kinematic, and architectural (stratigraphic) data, this study documents planform and vertical scaling relationships for submarine channels. We also compare these scaling relationships to subaerial channels (i.e., rivers) to illustrate differences and similarities in morphology and architecture. Using modern bathymetric, high-resolution 3D seismic, core/well, and outcrop data, we have developed an extensive database of planform and vertical channel scales and measurement metrics for submarine channels. Multiple scales of channelized features were extracted and analyzed, including: the geomorphic channel form, oxbow-cutoffs, channel trajectory/mobility, and preserved deposit thickness. Geometric statistics resulting from these features were used to derive scaling relationships relevant to reservoir characterization. These scaling relationships are coupled with additional data (e.g., basin type, slope morphology, net-to-gross) to identify and highlight the first order physical controls on channel morphology, kinematics, and resultant architecture. These controls form the basis for a classification of submarine channels that is objective and quantitative. This classification system is process-based and allows for the prediction of scale, architecture, and heterogeneity of submarine channel deposits of all scales. Subaerial and and submarine channels exhibit qualitatively similar morphology, but their stratigraphic record is known to be quite different. Submarine channel scaling relationships use many of the same metrics as those developed for river systems, allowing for the quantification of differences and similarities. These scaling relationships are highly relevant in both exploration and development settings, where they aid in volumetric analysis as well as heterogeneity prediction and reservoir model construction. Panel_14859 Panel_14859 3:45 PM 4:05 PM

In the fluvial sedimentary record sinuous channels and their associated fills are typically manifest as laterally-accreting point bar deposits. In the deep-marine, observations in modern systems and high-resolution seismic time slices indicate that channels there too are commonly sinuous. However, much less frequently reported from the modern or ancient sedimentary records are the associated meter- to several meter-scale laterally-spaced features that typify fluvial lateral accretion surfaces. In the Neoproterozoic Windermere Supergroup (WSG) exceptional exposure and vertically-dipping strata allow the easy recognition of surfaces resembling lateral accretion surfaces in a number of channel fills. These deposits tend to form at the top of much larger, aggradationally-filled (sinuous) channels, or as isolated clusters. Channel fills are 10-15 m thick and consist of amalgamated beds of decimeter-thick, very coarse sandstone/granule conglomerate. These strata, then, are overlain abruptly vertically and obliquely-upward by mudstone interbedded with thin-bedded turbidites. These finer, thinner strata are interpreted to be the inner-bend levee deposits onto which the channel-filling, thicker-bedded, coarser grained strata onlap. Moreover, the successive several-meter-scale lateral-offset stacking of these strata is interpreted to be caused by the continuous lateral migration of a single channel. This, then, begs the question as to why this style of channel filling is common here, but uncommon in much of the deep-marine sedimentary record. Laterally-accreting channels in the WSG are typically filled with very coarse sandstone, granule and even rare pebble conglomerate. These strata are notably coarser than those that fill the many other WSG channels that lack lateral accretion. The coarseness, but also the bimodal grain size distribution of the sediment supply, is interpreted to have had two interrelated consequences: channelized flows were highly density stratified, and accordingly most of the flow’s momentum resided in the basalmost part of the flow. This, then, enhanced erosion along the outer bend, which in turn promoted active lateral migration of the channel. The general lack of well-developed lateral accretion in the deep-marine sedimentary record, therefore, may simply be the general lack of a sufficiently coarse and bimodally distributed sediment supply to alter the structure of the channelized flows and encourage lateral channel migration. In the fluvial sedimentary record sinuous channels and their associated fills are typically manifest as laterally-accreting point bar deposits. In the deep-marine, observations in modern systems and high-resolution seismic time slices indicate that channels there too are commonly sinuous. However, much less frequently reported from the modern or ancient sedimentary records are the associated meter- to several meter-scale laterally-spaced features that typify fluvial lateral accretion surfaces. In the Neoproterozoic Windermere Supergroup (WSG) exceptional exposure and vertically-dipping strata allow the easy recognition of surfaces resembling lateral accretion surfaces in a number of channel fills. These deposits tend to form at the top of much larger, aggradationally-filled (sinuous) channels, or as isolated clusters. Channel fills are 10-15 m thick and consist of amalgamated beds of decimeter-thick, very coarse sandstone/granule conglomerate. These strata, then, are overlain abruptly vertically and obliquely-upward by mudstone interbedded with thin-bedded turbidites. These finer, thinner strata are interpreted to be the inner-bend levee deposits onto which the channel-filling, thicker-bedded, coarser grained strata onlap. Moreover, the successive several-meter-scale lateral-offset stacking of these strata is interpreted to be caused by the continuous lateral migration of a single channel. This, then, begs the question as to why this style of channel filling is common here, but uncommon in much of the deep-marine sedimentary record. Laterally-accreting channels in the WSG are typically filled with very coarse sandstone, granule and even rare pebble conglomerate. These strata are notably coarser than those that fill the many other WSG channels that lack lateral accretion. The coarseness, but also the bimodal grain size distribution of the sediment supply, is interpreted to have had two interrelated consequences: channelized flows were highly density stratified, and accordingly most of the flow’s momentum resided in the basalmost part of the flow. This, then, enhanced erosion along the outer bend, which in turn promoted active lateral migration of the channel. The general lack of well-developed lateral accretion in the deep-marine sedimentary record, therefore, may simply be the general lack of a sufficiently coarse and bimodally distributed sediment supply to alter the structure of the channelized flows and encourage lateral channel migration. Panel_14865 Panel_14865 4:05 PM 4:25 PM

Observations from outcrop, modern and subsurface datasets indicate that key regressive surfaces formed during phases of submarine slope degradation are time transgressive. These include levee deposits overlying lobes, composite erosion surfaces recording multiple phases of cut and fill, and hanging valleys and cut-off sinuous bends. Progressive confinement on the slope results in sequential sediment gravity flows maintaining their downslope energy farther into the basin during the initial period of slope channel system evolution. In this way, frontal lobes are continuously incised and overlain by external levees as the channel system propagates farther into the basin and becomes more confined at a reference point on the slope by a combination of substrate erosion and levee construction. The stratigraphic response of the linked basin floor fan is growth and net progradation until a maximum basinward extent is reached, corresponding to the time of most efficient slope sediment supply, which marks a maximum regressive surface. Conceptually, this process response could be autocyclic, but would be amplified with an allogenically-driven waxing-then-waning sediment supply cycle. The coupled progressive confinement of the slope channel system and basinward growth of submarine fans will result in a strongly diachronous lithological basal surface to the system and the widespread downstream transition from levee deposits to lobe deposits. This challenges the widely applied lowstand model whereby the deep-water sequence boundary is isochronous and passes into a correlative conformity at the base of the basin floor fan. Observations from outcrop, modern and subsurface datasets indicate that key regressive surfaces formed during phases of submarine slope degradation are time transgressive. These include levee deposits overlying lobes, composite erosion surfaces recording multiple phases of cut and fill, and hanging valleys and cut-off sinuous bends. Progressive confinement on the slope results in sequential sediment gravity flows maintaining their downslope energy farther into the basin during the initial period of slope channel system evolution. In this way, frontal lobes are continuously incised and overlain by external levees as the channel system propagates farther into the basin and becomes more confined at a reference point on the slope by a combination of substrate erosion and levee construction. The stratigraphic response of the linked basin floor fan is growth and net progradation until a maximum basinward extent is reached, corresponding to the time of most efficient slope sediment supply, which marks a maximum regressive surface. Conceptually, this process response could be autocyclic, but would be amplified with an allogenically-driven waxing-then-waning sediment supply cycle. The coupled progressive confinement of the slope channel system and basinward growth of submarine fans will result in a strongly diachronous lithological basal surface to the system and the widespread downstream transition from levee deposits to lobe deposits. This challenges the widely applied lowstand model whereby the deep-water sequence boundary is isochronous and passes into a correlative conformity at the base of the basin floor fan. Panel_14861 Panel_14861 4:25 PM 4:45 PM

Panel_14479 Panel_14479 1:15 PM 5:05 PM

Panel_15819 Panel_15819 1:15 PM 12:00 AM

The occurences of larger magnitude events (M>0) associated with hydraulic fracture stimulations may pose concerns from both a public perception and an engineering perspective. Through the use of a unique hybrid seismic recording network, we investigate the fracture characteristics of these induced-triggered events by examining both the dynamics of the sub-fracture failures during the rupture process and growth of the overall fracture from initiation to rupture arrest. This was achieved by incorporating both high frequency recordings utilizing 15 Hz omni-directional geophones situated in close proximity to the reservoir and thereby the point of rupture initiation and near surface low frequency recordings obtained using force balance accelerometers (0.1Hz) and geophones (4.5Hz) that allowed for the investigation of overall rupture characteristics. By utilizing such a recording network, we were able to examine different aspects of the rupture processes, including the role of asperities, roughness, the role of fluids and the failure mechanisms (shearing versus tensile dominance of behavior) associated with these induced-triggred events. Our initial results suggests that overall shearing is the dominant mode of failure, whereas the rupture characteristics of the sub-fracture failures are more complex than a simple shearing process and include a strong tensile component of failure. Our measurements of rupture complexity, seismic efficiency, rupture velocity and estimates of stress release further support the idea that the sub-fractures are characterized by the failure of multiple asperities that exhibit self-similar behaviour within themselves. These observations are part of ongoing investigations that may allow for the assessment of conditions under which induced-triggered failures may occur. By comparing events originating within the reservoir with those occurring outside the injection volume during the stimulation we also will assess whether the role of fluids can be identified and if the observed signatures uniquely characterize induced versus triggered behavior thereby allowing for the distinction between event types. The occurences of larger magnitude events (M>0) associated with hydraulic fracture stimulations may pose concerns from both a public perception and an engineering perspective. Through the use of a unique hybrid seismic recording network, we investigate the fracture characteristics of these induced-triggered events by examining both the dynamics of the sub-fracture failures during the rupture process and growth of the overall fracture from initiation to rupture arrest. This was achieved by incorporating both high frequency recordings utilizing 15 Hz omni-directional geophones situated in close proximity to the reservoir and thereby the point of rupture initiation and near surface low frequency recordings obtained using force balance accelerometers (0.1Hz) and geophones (4.5Hz) that allowed for the investigation of overall rupture characteristics. By utilizing such a recording network, we were able to examine different aspects of the rupture processes, including the role of asperities, roughness, the role of fluids and the failure mechanisms (shearing versus tensile dominance of behavior) associated with these induced-triggred events. Our initial results suggests that overall shearing is the dominant mode of failure, whereas the rupture characteristics of the sub-fracture failures are more complex than a simple shearing process and include a strong tensile component of failure. Our measurements of rupture complexity, seismic efficiency, rupture velocity and estimates of stress release further support the idea that the sub-fractures are characterized by the failure of multiple asperities that exhibit self-similar behaviour within themselves. These observations are part of ongoing investigations that may allow for the assessment of conditions under which induced-triggered failures may occur. By comparing events originating within the reservoir with those occurring outside the injection volume during the stimulation we also will assess whether the role of fluids can be identified and if the observed signatures uniquely characterize induced versus triggered behavior thereby allowing for the distinction between event types. Panel_15435 Panel_15435 1:20 PM 1:40 PM

3D seismic surveys in the Appalachian Basin of western PA reveal relatively short-segmented, orogen-parallel fault systems linked by relay ramps at step-overs in the Onondaga/Marcellus and successive units. Swings and disruptions in anticlinal traces mapped at the surface and in shallow coal and oil/gas fields correspond to the locations of the relay ramps. These relay ramps have characteristics typical of extensional relay ramps (for example they have overlap length to width ratios ranging from 1-3.5). The extensional faults initiated in Acadian times and are related to slip on and movement of the deeper Vernon shales and the Salina salts, partly guided by reactivated Iapetan-opening faults that may have influenced the slope and provided pathways for fluid migration. These extensional faults later developed as generally east-verging reverse faults higher in the section. To the extent of the 3D seismic surveys, the individual fault segments are straight. How does that observation compare with the oroclinic bend of the Pennsylvania salient where the folds appear to bend around the orocline? In a region where the fold axes have a sharp bend in map view a 3D survey shows the set of orogen-parallel faults that extend to the SW are abutted by a set with a more easterly trend that extend to the NE. The faults do not bend into the different alignments—they are two different sets. This fault set intersection is consistent geometrically with earlier suggestions that the orocline resulted (at least in part) from differently oriented and timed SHmax. In contrast, the nature of stepovers is less clear in the Ordovician Utica of the Mohawk Valley region in eastern NYS near the convergence zone of the Taconics. Fault segments linked by cross-fault stepovers observed in surface mapping (e.g., the Little Falls, Dolgeville, and more eastern NNE-striking faults). However, relay ramps have not been recognized, perhaps because of poor outcrop, or that there is none. One stepover of the Little Falls Fault is a narrow horse with nearly vertical bedding and tight fracture cleavage, suggesting that a relay ramp of consequence does not exist there. Lineaments that extend beyond the stepovers are colinear with proposed WNW-striking faults, some of which reflect local fabrics in pC. In 3D seismic surveys, stepovers on NNE-striking faults appear to be rhombochasms, suggesting right-lateral slip in Trenton/Utica time; surface geology could reflect such rhombochasms. 3D seismic surveys in the Appalachian Basin of western PA reveal relatively short-segmented, orogen-parallel fault systems linked by relay ramps at step-overs in the Onondaga/Marcellus and successive units. Swings and disruptions in anticlinal traces mapped at the surface and in shallow coal and oil/gas fields correspond to the locations of the relay ramps. These relay ramps have characteristics typical of extensional relay ramps (for example they have overlap length to width ratios ranging from 1-3.5). The extensional faults initiated in Acadian times and are related to slip on and movement of the deeper Vernon shales and the Salina salts, partly guided by reactivated Iapetan-opening faults that may have influenced the slope and provided pathways for fluid migration. These extensional faults later developed as generally east-verging reverse faults higher in the section. To the extent of the 3D seismic surveys, the individual fault segments are straight. How does that observation compare with the oroclinic bend of the Pennsylvania salient where the folds appear to bend around the orocline? In a region where the fold axes have a sharp bend in map view a 3D survey shows the set of orogen-parallel faults that extend to the SW are abutted by a set with a more easterly trend that extend to the NE. The faults do not bend into the different alignments—they are two different sets. This fault set intersection is consistent geometrically with earlier suggestions that the orocline resulted (at least in part) from differently oriented and timed SHmax. In contrast, the nature of stepovers is less clear in the Ordovician Utica of the Mohawk Valley region in eastern NYS near the convergence zone of the Taconics. Fault segments linked by cross-fault stepovers observed in surface mapping (e.g., the Little Falls, Dolgeville, and more eastern NNE-striking faults). However, relay ramps have not been recognized, perhaps because of poor outcrop, or that there is none. One stepover of the Little Falls Fault is a narrow horse with nearly vertical bedding and tight fracture cleavage, suggesting that a relay ramp of consequence does not exist there. Lineaments that extend beyond the stepovers are colinear with proposed WNW-striking faults, some of which reflect local fabrics in pC. In 3D seismic surveys, stepovers on NNE-striking faults appear to be rhombochasms, suggesting right-lateral slip in Trenton/Utica time; surface geology could reflect such rhombochasms. Panel_15443 Panel_15443 1:40 PM 2:00 PM

In this paper we will present an innovative multi-disciplinary workflow based on a structural modeling technique, ‘Complex Geometry fields’, that enables a geologist to generate attribute predictors for fracture densities such as detailed bedding geometry, curvature, dip and strain across an asset or basin. We will explain and demonstrate how this technique can be used to benefit the operators of unconventional assets in the following way; the attribute predictors can be used to ‘map out’ an estimate of the fracture density distributions in three dimensions in a study area which, in turn, can be used to optimally orient laterals well sections. The orientation of the laterals well sections with respect to the best estimate of the natural fracture orientation trends is thought to be of critical importance when designing completions and induced hydraulic fracture operations that ultimately control the flow of hydrocarbons into the well bore and thence to surface facilities. The computations to generate these geometry fields and predictors are based on the geometry of interpreted surfaces using established kinematic models such as vertical/oblique shear and flexural slip that account for compressional or extensional tectonic regimes and also the geo-mechanical lithological competency of the target formations. A good understanding of the structural components of the basin architecture are critical not just for hydrocarbon maturity but also in terms of understanding the behavior or natural and induced fracturing and faulting. After the structural geology attributes have been computed this information is then combined with and calibrated to other useful information such as 3D azimuthal seismic attributes or petrophysical and geomechanical observations derived from well locations to give the highest degree of accuracy with respect to predicting the gross distribution of the regional stress state and therefore understanding the associated development of fracture densities. The applications of creating a multi-disciplinary 3D numerical model of the subsurface that is enriched with this regional structural geology component are wide reaching but really benefits completion and hydraulic fracturing design as well as full field well planning strategies and the associated logistics because you have generated a high fidelity prediction of the subsurface across your entire asset. In this paper we will present an innovative multi-disciplinary workflow based on a structural modeling technique, ‘Complex Geometry fields’, that enables a geologist to generate attribute predictors for fracture densities such as detailed bedding geometry, curvature, dip and strain across an asset or basin. We will explain and demonstrate how this technique can be used to benefit the operators of unconventional assets in the following way; the attribute predictors can be used to ‘map out’ an estimate of the fracture density distributions in three dimensions in a study area which, in turn, can be used to optimally orient laterals well sections. The orientation of the laterals well sections with respect to the best estimate of the natural fracture orientation trends is thought to be of critical importance when designing completions and induced hydraulic fracture operations that ultimately control the flow of hydrocarbons into the well bore and thence to surface facilities. The computations to generate these geometry fields and predictors are based on the geometry of interpreted surfaces using established kinematic models such as vertical/oblique shear and flexural slip that account for compressional or extensional tectonic regimes and also the geo-mechanical lithological competency of the target formations. A good understanding of the structural components of the basin architecture are critical not just for hydrocarbon maturity but also in terms of understanding the behavior or natural and induced fracturing and faulting. After the structural geology attributes have been computed this information is then combined with and calibrated to other useful information such as 3D azimuthal seismic attributes or petrophysical and geomechanical observations derived from well locations to give the highest degree of accuracy with respect to predicting the gross distribution of the regional stress state and therefore understanding the associated development of fracture densities. The applications of creating a multi-disciplinary 3D numerical model of the subsurface that is enriched with this regional structural geology component are wide reaching but really benefits completion and hydraulic fracturing design as well as full field well planning strategies and the associated logistics because you have generated a high fidelity prediction of the subsurface across your entire asset. Panel_15442 Panel_15442 2:00 PM 2:20 PM

We report progress on a project to create a detailed map of in situ stress orientations and relative magnitudes throughout the state of Oklahoma. Over the past 5 years, seismicity has increased remarkably in much of the state, apparently related to significant increases in waste water injection. The purpose of this project is to develop detailed knowledge of the stress field in the state to identify which pre-existing faults could be potentially active in response to injection-related pore pressure increases. Over 50 new stress orientations have been obtained, utilizing wellbore image data and shear velocity anisotropy measurements from sonic dipole data provided by the oil and gas industry. These data reveal a very uniform ENE direction of maximum compressive stress through much of the state. As earthquake focal plane mechanisms generally indicate strike-slip faulting, the stress orientation data identify which pre-existing faults are potentially active. The data are consistent with slip on the near-vertical, NE-trending fault associated with at least one of the M 5+ earthquakes in the Prague, OK sequence in 2011. If successful, it would demonstrate that combining detailed information about pre-existing faults and the current stress field could be used to guide the siting of injection wells so as to decrease the potential for injection-related seismicity. We report progress on a project to create a detailed map of in situ stress orientations and relative magnitudes throughout the state of Oklahoma. Over the past 5 years, seismicity has increased remarkably in much of the state, apparently related to significant increases in waste water injection. The purpose of this project is to develop detailed knowledge of the stress field in the state to identify which pre-existing faults could be potentially active in response to injection-related pore pressure increases. Over 50 new stress orientations have been obtained, utilizing wellbore image data and shear velocity anisotropy measurements from sonic dipole data provided by the oil and gas industry. These data reveal a very uniform ENE direction of maximum compressive stress through much of the state. As earthquake focal plane mechanisms generally indicate strike-slip faulting, the stress orientation data identify which pre-existing faults are potentially active. The data are consistent with slip on the near-vertical, NE-trending fault associated with at least one of the M 5+ earthquakes in the Prague, OK sequence in 2011. If successful, it would demonstrate that combining detailed information about pre-existing faults and the current stress field could be used to guide the siting of injection wells so as to decrease the potential for injection-related seismicity. Panel_15441 Panel_15441 2:20 PM 2:40 PM

Panel_15734 Panel_15734 2:40 PM 12:00 AM

The Permian to Cretaceous Mid-Polish Trough was filled with several kilometers of Permian and Mesozoic sediments, including thick Zechstein (approx. Upper Permian) salts, and was completely inverted in Late Cretaceous - Paleogene times. The presence of thick salts gave rise to the development of a complex system of salt structures. Salt pillows and reactive diapirs started to form in early Triassic, triggered at least in part by regional basement faulting. In the Late Triassic some of the salt pillows reached diapiric stage. After their further growth in Jurassic to Early Cretaceous times, salt structures were compressionally reactived during regional inversion of the Mid-Polish Trough. Continuous growth of salt structures strongly controlled Mesozoic depositional systems, with thinner sedimentary cover characterized by generally shallower facies developed above salt structures, and larger thickness and deeper facies located within the intervening synclines. The most complex salt structures are known from the central, Kuiavian segment of the Mid-Polish Trough, where the large Klodawa salt diapir is located along with by several salt pillows and other smaller diapirs. In this area, various unconventional exploration targets have been identified. Middle Jurassic Dogger shales are 42m to 154m thick, with TOC’s in the 1% - 3% range. The Upper Jurassic Kimmeridgian shale is between 72m and 123m thick, with TOC’s up to 4.5%. Thermal modeling and Ro data indicate that shales are in the oil window in the syncline adjacent to the Klodawa diapir. Oil in open fractures has been frequently noted in the Tithonian carbonates (35m-116m thick) that lie directly above the organic-rich Kimmeridgian shale. Reprocessed legacy and newly acquired high-resolution 2D data seismic data, calibrated by deep wells, allows better constraints on the timing of salt-structure growth and, as a consequence, the evolution of the source rock. Cross-section construction and restoration suggest that basement faulting beneath the Klodawa diapir exerted significant control on the evolution of the Mesozoic petroleum system; thin-skinned supra-salt syn- and post-depositional faulting also played important though more local roles. The results of seismic inversion, seismic attribute analysis and seismic stratigraphic modelling provide information on lateral facies and thickness variations and on the inferred TOC changes within the prospective target zones. The Permian to Cretaceous Mid-Polish Trough was filled with several kilometers of Permian and Mesozoic sediments, including thick Zechstein (approx. Upper Permian) salts, and was completely inverted in Late Cretaceous - Paleogene times. The presence of thick salts gave rise to the development of a complex system of salt structures. Salt pillows and reactive diapirs started to form in early Triassic, triggered at least in part by regional basement faulting. In the Late Triassic some of the salt pillows reached diapiric stage. After their further growth in Jurassic to Early Cretaceous times, salt structures were compressionally reactived during regional inversion of the Mid-Polish Trough. Continuous growth of salt structures strongly controlled Mesozoic depositional systems, with thinner sedimentary cover characterized by generally shallower facies developed above salt structures, and larger thickness and deeper facies located within the intervening synclines. The most complex salt structures are known from the central, Kuiavian segment of the Mid-Polish Trough, where the large Klodawa salt diapir is located along with by several salt pillows and other smaller diapirs. In this area, various unconventional exploration targets have been identified. Middle Jurassic Dogger shales are 42m to 154m thick, with TOC’s in the 1% - 3% range. The Upper Jurassic Kimmeridgian shale is between 72m and 123m thick, with TOC’s up to 4.5%. Thermal modeling and Ro data indicate that shales are in the oil window in the syncline adjacent to the Klodawa diapir. Oil in open fractures has been frequently noted in the Tithonian carbonates (35m-116m thick) that lie directly above the organic-rich Kimmeridgian shale. Reprocessed legacy and newly acquired high-resolution 2D data seismic data, calibrated by deep wells, allows better constraints on the timing of salt-structure growth and, as a consequence, the evolution of the source rock. Cross-section construction and restoration suggest that basement faulting beneath the Klodawa diapir exerted significant control on the evolution of the Mesozoic petroleum system; thin-skinned supra-salt syn- and post-depositional faulting also played important though more local roles. The results of seismic inversion, seismic attribute analysis and seismic stratigraphic modelling provide information on lateral facies and thickness variations and on the inferred TOC changes within the prospective target zones. Panel_15440 Panel_15440 3:25 PM 3:45 PM

Several giant oilfields were discovered in the Barmer Basin in 2004, predominantly situated within the crests of faulted blocks, and the basin is now an established oil and gas producing province (7.3 BBL of STOIIP, 200,000bopd production). However, the extent and geometry of many fault-blocks within the rift are controlled by poorly understood rift-oblique faults that are variably imaged throughout the subsurface. Here we present a study of Lower Cretaceous sedimentology that accumulated prior to the main rifting event in the Barmer Basin, exposed along the eastern rift margin in the Sarnoo Hills, along with a detailed investigation of a rift-oblique fault network that is exposed nowhere else in the region. The findings provide critical insights into the structural evolution of the Barmer Basin and regional tectonic processes hitherto unrecognised. Lower Cretaceous sediments were deposited within an alluvial plain fluvial system. The high proportion of floodplain mudstones and siltstones preserved within the fluvial succession, and the lack of evidence for long-term floodplain stability, suggest aggradation of the floodplain, possibly due to rapid subsidence or a high sediment supply. Subsequent to deposition, brittle deformational structures accommodated northwest-southeast extension, highly oblique within the north-northwest trending Barmer Basin and previously unrecognised in northwest India. Despite the pre-rift tectono-stratigraphical relationship between the sedimentary succession and the fault network exposed at outcrop, the sedimentology suggests deposition was triggered by the onset of rapid subsidence in the Barmer region during the Lower Cretaceous, and is likely a manifestation of the rift-oblique (? NW-SE) extensional tectonics exposed. The identification of Lower Cretaceous, rift-oblique extension that pre-dated the main rifting event in the Barmer Basin during the Paleogene, indicates the present day structural architecture of the Barmer Basin resulted from two, superimposed, non-coaxial extensional events, and elucidates poorly understood rift-oblique faults interpreted in the subsurface throughout the rift. Integration of the findings with the currently understood regional tectonic framework suggest northwest-southeast orientated Lower Cretaceous extension is an intra-continental manifestation of transtension between the Greater Indian and Madagascan continents during Gondwana fragmentation. Several giant oilfields were discovered in the Barmer Basin in 2004, predominantly situated within the crests of faulted blocks, and the basin is now an established oil and gas producing province (7.3 BBL of STOIIP, 200,000bopd production). However, the extent and geometry of many fault-blocks within the rift are controlled by poorly understood rift-oblique faults that are variably imaged throughout the subsurface. Here we present a study of Lower Cretaceous sedimentology that accumulated prior to the main rifting event in the Barmer Basin, exposed along the eastern rift margin in the Sarnoo Hills, along with a detailed investigation of a rift-oblique fault network that is exposed nowhere else in the region. The findings provide critical insights into the structural evolution of the Barmer Basin and regional tectonic processes hitherto unrecognised. Lower Cretaceous sediments were deposited within an alluvial plain fluvial system. The high proportion of floodplain mudstones and siltstones preserved within the fluvial succession, and the lack of evidence for long-term floodplain stability, suggest aggradation of the floodplain, possibly due to rapid subsidence or a high sediment supply. Subsequent to deposition, brittle deformational structures accommodated northwest-southeast extension, highly oblique within the north-northwest trending Barmer Basin and previously unrecognised in northwest India. Despite the pre-rift tectono-stratigraphical relationship between the sedimentary succession and the fault network exposed at outcrop, the sedimentology suggests deposition was triggered by the onset of rapid subsidence in the Barmer region during the Lower Cretaceous, and is likely a manifestation of the rift-oblique (? NW-SE) extensional tectonics exposed. The identification of Lower Cretaceous, rift-oblique extension that pre-dated the main rifting event in the Barmer Basin during the Paleogene, indicates the present day structural architecture of the Barmer Basin resulted from two, superimposed, non-coaxial extensional events, and elucidates poorly understood rift-oblique faults interpreted in the subsurface throughout the rift. Integration of the findings with the currently understood regional tectonic framework suggest northwest-southeast orientated Lower Cretaceous extension is an intra-continental manifestation of transtension between the Greater Indian and Madagascan continents during Gondwana fragmentation. Panel_15439 Panel_15439 3:45 PM 4:05 PM

Displacement in seismically-active fault zones is frequently localized within narrow (<0.1 m) principal slip zones composed of nanogranular fault rock. We report on sheared simulated calcite fault gouges recovered from direct shear experiments performed (nominally) dry, using an (effective) normal stress of 50 MPa, temperatures of 18-150°C, and sliding velocities of 0.1-10 µm/s. The mechanical data show a transition from stable velocity strengthening slip below ~80°C, to potentially unstable, velocity weakening slip at higher temperatures. After each experiment, all sheared samples split along a shear band fabric defined by mainly R1- and boundary shears. Thin sections prepared normal to the shear plane and parallel to the shear direction, investigated using a light microscope, show that the shear bands are 10-100 µm wide and characterized by an ultra-fine (nanoscale) grain size and a strong optical anisotropy indicative of a crystallographic preferred orientation (CPO). Loose sample fragments recovered from the direct-shear piston interface, viewed normal to the shear plane, show elongate, shiny, striated patches aligned parallel to the shear direction, corresponding with the ultra-fine grained boundary-parallel bands seen in thin section. Focused ion beam – scanning electron microscopy (FIB-SEM) revealed that these “mirror-like” slip surfaces consist of ultra-fine grained films composed of ~100 nm wide fibers aligned sub-parallel to the shear direction, overlain or juxtaposed by granular zones of ~100 nm spherules constituting the shear band. The nanofibers are demonstrably ductile at room conditions, and show extreme extensibility and fracturing without localized necking, characteristic for superplasticity. Transmission electron microscopy (TEM) applied to isolated nanofibers revealed the presence of similarly oriented, 5-20 nm calcite nanocrystallites. Our results point to a fault slip deformation process involving competition between granular flow and diffusive mass transport operating at the nanoscale, suggesting that (potentially unstable) velocity weakening slip is produced by enhanced diffusion-driven compaction rates at elevated temperatures. We argue that the nanofibers and CPO are formed by a process of orientation-dependent nanoparticle sintering. Given the abundant recent observations of nanogranular fault surfaces in tectonically-active terrains, the proposed mechanism may be relevant to crustal seismogenesis in general. Displacement in seismically-active fault zones is frequently localized within narrow (<0.1 m) principal slip zones composed of nanogranular fault rock. We report on sheared simulated calcite fault gouges recovered from direct shear experiments performed (nominally) dry, using an (effective) normal stress of 50 MPa, temperatures of 18-150°C, and sliding velocities of 0.1-10 µm/s. The mechanical data show a transition from stable velocity strengthening slip below ~80°C, to potentially unstable, velocity weakening slip at higher temperatures. After each experiment, all sheared samples split along a shear band fabric defined by mainly R1- and boundary shears. Thin sections prepared normal to the shear plane and parallel to the shear direction, investigated using a light microscope, show that the shear bands are 10-100 µm wide and characterized by an ultra-fine (nanoscale) grain size and a strong optical anisotropy indicative of a crystallographic preferred orientation (CPO). Loose sample fragments recovered from the direct-shear piston interface, viewed normal to the shear plane, show elongate, shiny, striated patches aligned parallel to the shear direction, corresponding with the ultra-fine grained boundary-parallel bands seen in thin section. Focused ion beam – scanning electron microscopy (FIB-SEM) revealed that these “mirror-like” slip surfaces consist of ultra-fine grained films composed of ~100 nm wide fibers aligned sub-parallel to the shear direction, overlain or juxtaposed by granular zones of ~100 nm spherules constituting the shear band. The nanofibers are demonstrably ductile at room conditions, and show extreme extensibility and fracturing without localized necking, characteristic for superplasticity. Transmission electron microscopy (TEM) applied to isolated nanofibers revealed the presence of similarly oriented, 5-20 nm calcite nanocrystallites. Our results point to a fault slip deformation process involving competition between granular flow and diffusive mass transport operating at the nanoscale, suggesting that (potentially unstable) velocity weakening slip is produced by enhanced diffusion-driven compaction rates at elevated temperatures. We argue that the nanofibers and CPO are formed by a process of orientation-dependent nanoparticle sintering. Given the abundant recent observations of nanogranular fault surfaces in tectonically-active terrains, the proposed mechanism may be relevant to crustal seismogenesis in general. Panel_15438 Panel_15438 4:05 PM 4:25 PM

Molles (MOF), Lajas (LJF) and Challacó (CHF) Formations consist of 1000 meters thick, second order transgressive-regressive mainly clastic sequences going from distal marine (MOF) to coastal (LJF) and continental environment (CHF). These units were deposited during Pleinsbachian to middle Callovian times and represent the first sedimentary record of Neuquén Basin. Huincul High is an east-west tectonic high, composed of several inverted Late Triassic half grabens as a result of several stages of oblique compressive tectonism (?1~30W°) during the Jurassic-Cretaceous. Historically, these inverted half grabens have been producing oil fields at this latitude since 30s. However, downdip into the basin these sequences are almost completely unexplored because of its depth (+4000mts) and the lack of good reservoir properties. In this study, we present a tectosedimentary evolution of early-middle Jurassic units based on multisurvey 3D seismic interpretation and more than 50 wells information over an area of 3000km2. Seismically, older sequences are composed of ~300m thick package, evolving from E-W to SE-NW prograding sigmoidal facies. Distal portions of these units, characterized by high amplitude and very continuous events, corresponds to TOC-riched distal marine facies (MOF). Slope and proximal positions are more chaotic and show lateral amplitude variations (LJF). Above these units, lies a 500 m thick aggrading, parallel seismic facies, composed of sand-shale alternations interpreted as coastal environment deposits (LJF). These sands intervals represent: a tight gas deep reservoir system in relative distal positions, and a shallow conventional reservoir system in more proximal locations. The Early Middle Jurassic unit ends with a 200 m-thick unit of continental deposits (CHF) interpreted as transparent seismic facies bounded at its top by the IntraCallovian angular unconformity. In the vecinity of the Huincul High, these sequences are completed eroded as a result of several tectonic compressive pulses, developing different types of structural and stratigraphic traps. Understanding the relationship between sedimentation and timing of the different tectonic events during this period is key in both exploration and development of these conventional and unconventional plays. Molles (MOF), Lajas (LJF) and Challacó (CHF) Formations consist of 1000 meters thick, second order transgressive-regressive mainly clastic sequences going from distal marine (MOF) to coastal (LJF) and continental environment (CHF). These units were deposited during Pleinsbachian to middle Callovian times and represent the first sedimentary record of Neuquén Basin. Huincul High is an east-west tectonic high, composed of several inverted Late Triassic half grabens as a result of several stages of oblique compressive tectonism (?1~30W°) during the Jurassic-Cretaceous. Historically, these inverted half grabens have been producing oil fields at this latitude since 30s. However, downdip into the basin these sequences are almost completely unexplored because of its depth (+4000mts) and the lack of good reservoir properties. In this study, we present a tectosedimentary evolution of early-middle Jurassic units based on multisurvey 3D seismic interpretation and more than 50 wells information over an area of 3000km². Seismically, older sequences are composed of ~300m thick package, evolving from E-W to SE-NW prograding sigmoidal facies. Distal portions of these units, characterized by high amplitude and very continuous events, corresponds to TOC-riched distal marine facies (MOF). Slope and proximal positions are more chaotic and show lateral amplitude variations (LJF). Above these units, lies a 500 m thick aggrading, parallel seismic facies, composed of sand-shale alternations interpreted as coastal environment deposits (LJF). These sands intervals represent: a tight gas deep reservoir system in relative distal positions, and a shallow conventional reservoir system in more proximal locations. The Early Middle Jurassic unit ends with a 200 m-thick unit of continental deposits (CHF) interpreted as transparent seismic facies bounded at its top by the IntraCallovian angular unconformity. In the vecinity of the Huincul High, these sequences are completed eroded as a result of several tectonic compressive pulses, developing different types of structural and stratigraphic traps. Understanding the relationship between sedimentation and timing of the different tectonic events during this period is key in both exploration and development of these conventional and unconventional plays. Panel_15437 Panel_15437 4:25 PM 4:45 PM

Panel_14499 Panel_14499 1:15 PM 2:40 PM

Panel_15768 Panel_15768 1:15 PM 12:00 AM

Water ice and other volatiles are vital in sustaining human settlement in space. Hydrogen and oxygen extracted from water by hydrogen-oxide reactions can be used as propellants on short-range interplanetary missions in the inner Solar System prior to developing more advanced propulsion systems for subsequent long-range interplanetary missions. The resource base for Martian water-ice and other volatiles far exceeds the resource base on the Moon and Mercury. Water ice occurs in abundance on Mars in polar ice caps, shallow permafrost, and in layered terrain adjacent to the poles. Martian permafrost, which holds more water ice than the poles, occurs as tropical mountain glaciers and in polygonal terrain with morphologies similar to those of terrestrial periglacial features. Subsurface ice on Mars has an areal distribution exceeding 20 million square kilometers, whereas the polar caps, although 2.7 and 3.1 km thick at the North and South Poles, respectively, each encompass an area <1 million square kilometers. Mars possesses sufficient water and volatile resources amenable to terraforming, although other volatiles from ammonia-rich comets can also be introduced artificially from human-induced impacts to accumulate greenhouse gases in the tenuous Martian atmosphere. At least four comets, each with a mass of 10 Gt (10 billion metric tons), would be required to trigger a Martian greenhouse effect. Moreover, in situ methods of constructing an artificial Martial atmosphere could involve greenhouse gas factories expelling halocarbon gases (CFC's), with 39 Mt (million metric tons) necessary to sublimate the southern carbon-dioxide ice cap. Other methods can involve deploying orbital reflection arrays with a collective mass of up to 200,000 tonnes to produce sufficient insolation for volatilizing the Martian polar caps. However, the lack of a robust magnetosphere is a major obstacle to successful terraforming of Mars, as solar flares could periodically strip away up to 30% of the newly created, sparse atmosphere. Best-case terraforming scenarios may require centuries, and the technology to construct a protective Martian electromagnetic field protection could involve a similar timescale. Water ice and other volatiles are vital in sustaining human settlement in space. Hydrogen and oxygen extracted from water by hydrogen-oxide reactions can be used as propellants on short-range interplanetary missions in the inner Solar System prior to developing more advanced propulsion systems for subsequent long-range interplanetary missions. The resource base for Martian water-ice and other volatiles far exceeds the resource base on the Moon and Mercury. Water ice occurs in abundance on Mars in polar ice caps, shallow permafrost, and in layered terrain adjacent to the poles. Martian permafrost, which holds more water ice than the poles, occurs as tropical mountain glaciers and in polygonal terrain with morphologies similar to those of terrestrial periglacial features. Subsurface ice on Mars has an areal distribution exceeding 20 million square kilometers, whereas the polar caps, although 2.7 and 3.1 km thick at the North and South Poles, respectively, each encompass an area <1 million square kilometers. Mars possesses sufficient water and volatile resources amenable to terraforming, although other volatiles from ammonia-rich comets can also be introduced artificially from human-induced impacts to accumulate greenhouse gases in the tenuous Martian atmosphere. At least four comets, each with a mass of 10 Gt (10 billion metric tons), would be required to trigger a Martian greenhouse effect. Moreover, in situ methods of constructing an artificial Martial atmosphere could involve greenhouse gas factories expelling halocarbon gases (CFC's), with 39 Mt (million metric tons) necessary to sublimate the southern carbon-dioxide ice cap. Other methods can involve deploying orbital reflection arrays with a collective mass of up to 200,000 tonnes to produce sufficient insolation for volatilizing the Martian polar caps. However, the lack of a robust magnetosphere is a major obstacle to successful terraforming of Mars, as solar flares could periodically strip away up to 30% of the newly created, sparse atmosphere. Best-case terraforming scenarios may require centuries, and the technology to construct a protective Martian electromagnetic field protection could involve a similar timescale. Panel_15633 Panel_15633 1:20 PM 1:40 PM

Compared to the Earth's cradle for humanity, Mars is a unique environment. It has a very low pressure atmosphere composed almost completely of carbon dioxide, about half the incident solar energy seen at Earth, an insignificant magnetic field where a large percentage of solar and cosmic radiation bathes the surface of the planet, and it has no water at the surface. Freezing is warm day on Mars. Not a very hospitable place for future exploration crews to live for as long as a year and a half. In the face of the obvious list of challenges, the first explorers will need to utilize Martian resources to maintain a habitable environment. With the surface exposed to solar and galactic radiation, some form of protected central facility will be required. Experience from the extended duration missions aboard the International Space Station will provide a portion of the countermeasures technology but a more fundamental technique will need to be employed by the surface geologists on Mars. Maintaining a biosphere supporting human life will also be a huge challenge. We take for granted the systems that support us here and, as a result, our knowledge of just how these systems interact to keep our biosphere functioning is incomplete. Martian geologists will need to create and sustain their own biosphere (soil, water, air, and living systems) and fully understand how it works. The presence of subsurface ice in recoverable quantities will supply not only metabolic needs but a source of oxygen for atmospheric conditioning and a potential source for rocket engines and fuel cells. The challenge will be to find minable resources. To do that an exploration system very similar to that commonly used here on Earth in hydrocarbon exploration will need to be developed to find these resources. Will the presence of minable water define the location of the future facility? If so, the resource distribution will need to be assessed prior to sending the teams. This paper will present some possible answers to these problems. Though there have been a number of what have been termed Martian analog experiences, none can fully expose the research teams to the true Martian environment. One of the few places that can get close will be on the Moon. For this, and other reasons, an extension of the lunar research program begun in the Apollo heroic phase of exploration needs to be an international space priority. Compared to the Earth's cradle for humanity, Mars is a unique environment. It has a very low pressure atmosphere composed almost completely of carbon dioxide, about half the incident solar energy seen at Earth, an insignificant magnetic field where a large percentage of solar and cosmic radiation bathes the surface of the planet, and it has no water at the surface. Freezing is warm day on Mars. Not a very hospitable place for future exploration crews to live for as long as a year and a half. In the face of the obvious list of challenges, the first explorers will need to utilize Martian resources to maintain a habitable environment. With the surface exposed to solar and galactic radiation, some form of protected central facility will be required. Experience from the extended duration missions aboard the International Space Station will provide a portion of the countermeasures technology but a more fundamental technique will need to be employed by the surface geologists on Mars. Maintaining a biosphere supporting human life will also be a huge challenge. We take for granted the systems that support us here and, as a result, our knowledge of just how these systems interact to keep our biosphere functioning is incomplete. Martian geologists will need to create and sustain their own biosphere (soil, water, air, and living systems) and fully understand how it works. The presence of subsurface ice in recoverable quantities will supply not only metabolic needs but a source of oxygen for atmospheric conditioning and a potential source for rocket engines and fuel cells. The challenge will be to find minable resources. To do that an exploration system very similar to that commonly used here on Earth in hydrocarbon exploration will need to be developed to find these resources. Will the presence of minable water define the location of the future facility? If so, the resource distribution will need to be assessed prior to sending the teams. This paper will present some possible answers to these problems. Though there have been a number of what have been termed Martian analog experiences, none can fully expose the research teams to the true Martian environment. One of the few places that can get close will be on the Moon. For this, and other reasons, an extension of the lunar research program begun in the Apollo heroic phase of exploration needs to be an international space priority. Panel_15631 Panel_15631 1:40 PM 2:00 PM

The Lunar Geophysical Network (LGN) mission is one of the space missions recently recommended to NASA by a panel of scientists assembled by the National Research Council. The LGN mission would deploy a ‘global, long-lived network of geophysical instruments on the Moon’ to collect seismic, heat flow, laser ranging and magnetic data. Our team of scientists and engineers are currently developing a heat flow probe suited for such a mission and the robotic and human missions to the Moon considered by other government agencies and private sectors (e.g., SELENE-2, Resource Prospector, Luna-Glob, Golden Spike). Our heat flow probe is a compact and modular system that can be deployed robotically on a small lander. It weighs less than 2 kg and use only 10 Watts of power. It is designed to reach 3-m below the lunar surface, 0.6 m deeper than reached by the heat flow probes on the Apollo missions. It obtains the heat flow by measuring thermal gradient and thermal conductivity of the depth interval of the regolith penetrated. The probe uses a pneumatic excavation system in deploying its thermal sensors to the subsurface. The deployment mechanism (~0.3 m long) spools out a glass fiber composite stem downward. The stem then forms a hollow cylinder of ~1.5-cm diameter, and subsequently pushes the penetrating cone into the regolith, while gas jets, emitted from the cone tip, blow away loosened materials. Removing material from the bottom of the hole allows the stem to advance with minimum thrust. A short (~1.5-cm), thin (2-mm diameter) thermal probe, attached to the cone tip, measures temperatures and thermal conductivities of the regolith by stopping for 30 minutes at different depths on the way down. During each stop, the system shuts off the gas jet and pushes the needle sensor into the undisturbed bottom-hole regolith. After the cone reaches the targeted depth, the temperature sensors embedded on the fully extended stem monitor long-term stability of the thermal gradient. Lab tests have been conducted in the last 3 years to refine the deployment mechanism and the sensor system. The latest prototype of a fully integrated system was able to penetrate nearly 2 meters into lunar regolith simulant in vacuum chamber. Further improvement is currently being made now to reach the targeted 3-m depth. The Lunar Geophysical Network (LGN) mission is one of the space missions recently recommended to NASA by a panel of scientists assembled by the National Research Council. The LGN mission would deploy a ‘global, long-lived network of geophysical instruments on the Moon’ to collect seismic, heat flow, laser ranging and magnetic data. Our team of scientists and engineers are currently developing a heat flow probe suited for such a mission and the robotic and human missions to the Moon considered by other government agencies and private sectors (e.g., SELENE-2, Resource Prospector, Luna-Glob, Golden Spike). Our heat flow probe is a compact and modular system that can be deployed robotically on a small lander. It weighs less than 2 kg and use only 10 Watts of power. It is designed to reach 3-m below the lunar surface, 0.6 m deeper than reached by the heat flow probes on the Apollo missions. It obtains the heat flow by measuring thermal gradient and thermal conductivity of the depth interval of the regolith penetrated. The probe uses a pneumatic excavation system in deploying its thermal sensors to the subsurface. The deployment mechanism (~0.3 m long) spools out a glass fiber composite stem downward. The stem then forms a hollow cylinder of ~1.5-cm diameter, and subsequently pushes the penetrating cone into the regolith, while gas jets, emitted from the cone tip, blow away loosened materials. Removing material from the bottom of the hole allows the stem to advance with minimum thrust. A short (~1.5-cm), thin (2-mm diameter) thermal probe, attached to the cone tip, measures temperatures and thermal conductivities of the regolith by stopping for 30 minutes at different depths on the way down. During each stop, the system shuts off the gas jet and pushes the needle sensor into the undisturbed bottom-hole regolith. After the cone reaches the targeted depth, the temperature sensors embedded on the fully extended stem monitor long-term stability of the thermal gradient. Lab tests have been conducted in the last 3 years to refine the deployment mechanism and the sensor system. The latest prototype of a fully integrated system was able to penetrate nearly 2 meters into lunar regolith simulant in vacuum chamber. Further improvement is currently being made now to reach the targeted 3-m depth. Panel_15634 Panel_15634 2:00 PM 2:20 PM

Previous analysis of various carbonaceous chondrites (CC) and comet dust by various scientists since 1960s, recent findings of abundance of water, oil and gas within various Saturn and Jupiter moons, and key geological features and methane on Mars may suggest the presence of abundant petroleum hydrocarbons within our Solar System. Recent geochemical and other analytical data of various CCs indicate that CCs are organic rich and contain abundant macromolecular components and oil like extractable biomarkers that closely resemble terrestrial hydrocarbon source rock kerogen and bitumen usually observed in shale and carbonates. The bacteriomorphic microstructures preserved in these CCs closely resemble remnant terrestrial palynomorphs of microbial (prokaryotic and archaeoprokaryotic) ecosystems established on Earth over 3.5 Ga ago. This data could be quite significant for future oil and gas prospects on Mars in future as the early geology of planet Mars and Earth are quite similar and both planets had water for a long period of time (except for the initial phase of planet formation). Similar to terrestrial oil-prone source rocks on Earth, these extraterrestrial palynomorphs and their geochemical signatures within the CCs (including from Mars) and comet dust thus could be linked to biogenic and thermogenic hydrocarbons in the Solar System. Consequently, the Solar system possibly represents a connected biosphere with transfers taking place on dynamic timescales in millions of years. Now the question that is before us is how life has been transported in various planets of the Solar System. It was suggested that life could be transported in the Solar System planets possibly either from the (a) purging the primordial “comet dust” or (b) slow impact of carbonaceous meteoritic showers. The presence of oil and gas in the deltaic, other deeper section of the Martian crust and atmosphere would be quite pertinent in developing the future greenhouse effect and human settlement on Mars. Previous analysis of various carbonaceous chondrites (CC) and comet dust by various scientists since 1960s, recent findings of abundance of water, oil and gas within various Saturn and Jupiter moons, and key geological features and methane on Mars may suggest the presence of abundant petroleum hydrocarbons within our Solar System. Recent geochemical and other analytical data of various CCs indicate that CCs are organic rich and contain abundant macromolecular components and oil like extractable biomarkers that closely resemble terrestrial hydrocarbon source rock kerogen and bitumen usually observed in shale and carbonates. The bacteriomorphic microstructures preserved in these CCs closely resemble remnant terrestrial palynomorphs of microbial (prokaryotic and archaeoprokaryotic) ecosystems established on Earth over 3.5 Ga ago. This data could be quite significant for future oil and gas prospects on Mars in future as the early geology of planet Mars and Earth are quite similar and both planets had water for a long period of time (except for the initial phase of planet formation). Similar to terrestrial oil-prone source rocks on Earth, these extraterrestrial palynomorphs and their geochemical signatures within the CCs (including from Mars) and comet dust thus could be linked to biogenic and thermogenic hydrocarbons in the Solar System. Consequently, the Solar system possibly represents a connected biosphere with transfers taking place on dynamic timescales in millions of years. Now the question that is before us is how life has been transported in various planets of the Solar System. It was suggested that life could be transported in the Solar System planets possibly either from the (a) purging the primordial “comet dust” or (b) slow impact of carbonaceous meteoritic showers. The presence of oil and gas in the deltaic, other deeper section of the Martian crust and atmosphere would be quite pertinent in developing the future greenhouse effect and human settlement on Mars. Panel_15632 Panel_15632 2:20 PM 2:40 PM

Panel_14485 Panel_14485 3:20 PM 5:05 PM

Panel_15769 Panel_15769 3:20 PM 12:00 AM

This is an invited paper presented by the Director of the Colorado Oil and Gas Conservation Commission. The presentation will discuss, in general terms, the respective roles of state and local government agencies in Colorado to regulate the oil and gas industry. The presentation will also cover ways in which citizens can and have participated in the regulatory, policy and political processes. The presentation will address recent events in Colorado concerning the increase in oil and gas development along the Front Range, which has resulted largely from development and deployment of two technologies: horizontal drilling and hydraulic fracturing. The presentation will discuss varied ways in which different constituencies have responded to the increased oil and gas development, including efforts to preclude the activity outright; cooperative agreements between local governments and oil and gas operators; and collaboration between the state regulatory agency and local governments. This is an invited paper presented by the Director of the Colorado Oil and Gas Conservation Commission. The presentation will discuss, in general terms, the respective roles of state and local government agencies in Colorado to regulate the oil and gas industry. The presentation will also cover ways in which citizens can and have participated in the regulatory, policy and political processes. The presentation will address recent events in Colorado concerning the increase in oil and gas development along the Front Range, which has resulted largely from development and deployment of two technologies: horizontal drilling and hydraulic fracturing. The presentation will discuss varied ways in which different constituencies have responded to the increased oil and gas development, including efforts to preclude the activity outright; cooperative agreements between local governments and oil and gas operators; and collaboration between the state regulatory agency and local governments. Panel_15495 Panel_15495 3:25 PM 3:45 PM

Significant concern has been expressed regarding the potential impact of shale gas extraction on surrounding drinking water resources. However, determining whether changes in groundwater chemistry (e.g., methane, salts, etc.) are natural in origin or caused by drilling operations can be difficult, particularly when a) different sampling and analytical methodologies are employed and b) water quality can vary naturally over time due to various factors (e.g., intensity of residential water use). To better understand the sources of variability in water quality in residential water wells in NE Pennsylvania, an area of active Marcellus shale gas extraction, two field studies were completed at nine residential water wells to evaluate the significance of sampling methodology and temporal variability on water quality results. For the sampling variability study, the effect of different sample collection methods and sampling containers on dissolved gas concentrations, as well as the effect of purge volume on dissolved gas concentrations, general water quality (e.g., sodium), and the isotopic signature of dissolved gases, water, and dissolved inorganic carbon was assessed. For the temporal variability study, water quality results from monthly sampling, as well as real-time data from a weather station and down-hole data loggers, were evaluated over an 18 month period to quantify the variability observed in measured parameters, identify relationships between parameters, and assess potential drivers of variability. Findings from these field programs improve our understanding of the inherent variability in pre- and post-drill results and offer insight into methods for improving sample collection protocols and data interpretation. Significant concern has been expressed regarding the potential impact of shale gas extraction on surrounding drinking water resources. However, determining whether changes in groundwater chemistry (e.g., methane, salts, etc.) are natural in origin or caused by drilling operations can be difficult, particularly when a) different sampling and analytical methodologies are employed and b) water quality can vary naturally over time due to various factors (e.g., intensity of residential water use). To better understand the sources of variability in water quality in residential water wells in NE Pennsylvania, an area of active Marcellus shale gas extraction, two field studies were completed at nine residential water wells to evaluate the significance of sampling methodology and temporal variability on water quality results. For the sampling variability study, the effect of different sample collection methods and sampling containers on dissolved gas concentrations, as well as the effect of purge volume on dissolved gas concentrations, general water quality (e.g., sodium), and the isotopic signature of dissolved gases, water, and dissolved inorganic carbon was assessed. For the temporal variability study, water quality results from monthly sampling, as well as real-time data from a weather station and down-hole data loggers, were evaluated over an 18 month period to quantify the variability observed in measured parameters, identify relationships between parameters, and assess potential drivers of variability. Findings from these field programs improve our understanding of the inherent variability in pre- and post-drill results and offer insight into methods for improving sample collection protocols and data interpretation. Panel_15494 Panel_15494 4:25 PM 4:45 PM

Oil and gas fields in the Uinta Basin of eastern Utah produced 27 million BO and 446 BCFG in 2013 from the Tertiary Wasatch and Green River Formations and several formations in the Upper Cretaceous Mesaverde Group. Over 105 million bbls of water was also produced with these hydrocarbons. Extensive drilling for lenticular, tight gas sands in the Wasatch and Mesaverde occurred in the eastern part of the basin, whereas large drilling programs as part of expanding waterflood projects for oil in the Green River continued in the south-central basin; 1550 wells were permitted in 2013. The environmentally sound disposal of produced water affects the economics of the hydrocarbon resource development in the basin. Specific Uinta Basin water issues include: water use/reuse for well drilling and completion (fracking), appropriate sites for disposal/reuse of water, development of systems to manage the produced water streams, and differing challenges for gas versus oil producers. Current produced water disposal practices in the Uinta Basin consist of (1) injection in deep wells below the base of a moderately saline aquifer in the Green River Formation, (2) storage and evaporation in lined disposal ponds, and (3) supplying water for flooding in enhanced-oil recovery (EOR) programs. Our study evaluated the thickness, structure, porosity, permeability, water quality, and temperature of all aquifer/reservoir units in the basin from the surface (alluvium) through the Jurassic Glen Canyon Group. From this evaluation, the Birds Nest Aquifer in the upper Green River is the most widespread and economically viable disposal unit in terms of depth, proximity to producing wells, and water quality. Statistical analysis of water production quantity and quality identified and forecasted volume trends. For example, the greatest need for water disposal results from drilling gas wells in the eastern part of the basin whereas water is needed for EOR projects in the south-central basin. These needs will continue, based on predicted drilling trends, and thus we suggest that excess compatible produced water from gas wells be transported to oil fields undergoing EOR. Produced water could also be used for fracking water as fracking is required for tight-gas sand and potential shale-gas reservoirs in the basin. Finally, the heat content of produced waters, although generally too low for power generation, could be used locally for space heating and engineering purposes. Oil and gas fields in the Uinta Basin of eastern Utah produced 27 million BO and 446 BCFG in 2013 from the Tertiary Wasatch and Green River Formations and several formations in the Upper Cretaceous Mesaverde Group. Over 105 million bbls of water was also produced with these hydrocarbons. Extensive drilling for lenticular, tight gas sands in the Wasatch and Mesaverde occurred in the eastern part of the basin, whereas large drilling programs as part of expanding waterflood projects for oil in the Green River continued in the south-central basin; 1550 wells were permitted in 2013. The environmentally sound disposal of produced water affects the economics of the hydrocarbon resource development in the basin. Specific Uinta Basin water issues include: water use/reuse for well drilling and completion (fracking), appropriate sites for disposal/reuse of water, development of systems to manage the produced water streams, and differing challenges for gas versus oil producers. Current produced water disposal practices in the Uinta Basin consist of (1) injection in deep wells below the base of a moderately saline aquifer in the Green River Formation, (2) storage and evaporation in lined disposal ponds, and (3) supplying water for flooding in enhanced-oil recovery (EOR) programs. Our study evaluated the thickness, structure, porosity, permeability, water quality, and temperature of all aquifer/reservoir units in the basin from the surface (alluvium) through the Jurassic Glen Canyon Group. From this evaluation, the Birds Nest Aquifer in the upper Green River is the most widespread and economically viable disposal unit in terms of depth, proximity to producing wells, and water quality. Statistical analysis of water production quantity and quality identified and forecasted volume trends. For example, the greatest need for water disposal results from drilling gas wells in the eastern part of the basin whereas water is needed for EOR projects in the south-central basin. These needs will continue, based on predicted drilling trends, and thus we suggest that excess compatible produced water from gas wells be transported to oil fields undergoing EOR. Produced water could also be used for fracking water as fracking is required for tight-gas sand and potential shale-gas reservoirs in the basin. Finally, the heat content of produced waters, although generally too low for power generation, could be used locally for space heating and engineering purposes. Panel_15497 Panel_15497 4:45 PM 5:05 PM

A panel including representatives from the Department of Energy (DOE), academia, industry and national lab will explain the planned subsurface research initiative and solicit feedback on fundamental and applied research needs. The subsurface provides a majority of the world’s energy and offers great potential for CO2, nuclear waste and energy storage. Despite decades of research, and recent successes in new extraction methods, subsurface energy resources overall are underutilized and environmental risks are not well integrated into strategies. The U.S. DOE and National Laboratories are advancing an innovative crosscutting Subsurface Initiative, focused on revolutionizing sustainable subsurface energy production and storage. This challenge will require transformational improvements in our ability to access, characterize, predict and adaptively manipulate fracture and flow processes over scales ranging from nanometers to kilometers. This town hall will describe and solicit community feedback on the initiative research priorities.

A panel including representatives from the Department of Energy (DOE), academia, industry and national lab will explain the planned subsurface research initiative and solicit feedback on fundamental and applied research needs.

The subsurface provides a majority of the world’s energy and offers great potential for CO2, nuclear waste and energy storage. Despite decades of research, and recent successes in new extraction methods, subsurface energy resources overall are underutilized and environmental risks are not well integrated into strategies. The U.S. DOE and National Laboratories are advancing an innovative crosscutting Subsurface Initiative, focused on revolutionizing sustainable subsurface energy production and storage. This challenge will require transformational improvements in our ability to access, characterize, predict and adaptively manipulate fracture and flow processes over scales ranging from nanometers to kilometers. This town hall will describe and solicit community feedback on the initiative research priorities.

Panel_14252 Panel_14252 5:10 PM 6:40 PM

Panel_15943 Panel_15943 5:10 PM 6:40 PM

Panel_14412 Panel_14412 1:15 PM 5:05 PM

Panel_15770 Panel_15770 1:15 PM 12:00 AM

The Upper Morrow sandstones in the western Anadarko Basin have been prolific oil producers for more than five decades. Exploration for Morrow reservoirs has a tradition of being high-risk but high-reward. Detection of Morrow sandstones is a major problem in the exploration for new fields and the characterization of existing fields because they are very thin and laterally discontinuous. The Postle field in Oklahoma is undergoing CO2 flood and for successful flood management it is important to characterize the Morrow A sandstone, which is the main reservoir in the study area. The S-wave velocity contrast between Morrow shale and A sandstone is strong as compared to P-wave velocity contrast, and therefore, multicomponent seismic data can help in characterizing these reservoirs. I have used P-impedance from prestack inversion of P data and the S-impedance and density from prestack inversion of SV data for interpretation in this paper. Stratal slicing method is used to get the P- and S-impedance and density maps. We find that the S-impedance map gives a better match with the Morrow A sandstone distribution as compared to the P-impedance map. The density estimation from prestack inversion of SV data is able to distinguish between low- and high-quality reservoirs. The porosity volume is estimated from density obtained from prestack S-wave inversion. The density and porosity maps obtained from seismic shows satisfactory match with the well log density and porosity maps. Some possible well locations are suggested based on the interpretation of inversion results. The Upper Morrow sandstones in the western Anadarko Basin have been prolific oil producers for more than five decades. Exploration for Morrow reservoirs has a tradition of being high-risk but high-reward. Detection of Morrow sandstones is a major problem in the exploration for new fields and the characterization of existing fields because they are very thin and laterally discontinuous. The Postle field in Oklahoma is undergoing CO₂ flood and for successful flood management it is important to characterize the Morrow A sandstone, which is the main reservoir in the study area. The S-wave velocity contrast between Morrow shale and A sandstone is strong as compared to P-wave velocity contrast, and therefore, multicomponent seismic data can help in characterizing these reservoirs. I have used P-impedance from prestack inversion of P data and the S-impedance and density from prestack inversion of SV data for interpretation in this paper. Stratal slicing method is used to get the P- and S-impedance and density maps. We find that the S-impedance map gives a better match with the Morrow A sandstone distribution as compared to the P-impedance map. The density estimation from prestack inversion of SV data is able to distinguish between low- and high-quality reservoirs. The porosity volume is estimated from density obtained from prestack S-wave inversion. The density and porosity maps obtained from seismic shows satisfactory match with the well log density and porosity maps. Some possible well locations are suggested based on the interpretation of inversion results. Panel_15599 Panel_15599 1:20 PM 1:40 PM

A common question asked by Geologist, Engineers and Geophysicists involved in unconventional resource plays is “can multi-component 3D seismic help in my onshore exploration effort”. The question has been answered in offshore exploration with numerous examples of reservoir improvements associated with gas clouds and low P-wave impedance contrasts. This paper answers this question for onshore unconventional plays using the Marcellus Shale as an example. It shows that using shear-wave measurements recorded from multi-component 3D seismic, provides better characterization enabling improved vertical resolution and lateral continuity of the Marcellus formation members, superior determination of geomechanical properties such as brittleness, and, good differentiation of density and TOC. This example uses a recent proprietary multi-component 3D recorded simultaneously with a large conventional 3D covering the thickest and highest TOC area in Bedford County, Pennsylvania, where Marcellus drilling activity is highest. The paper shows a comparison of the results obtained from a conventional elastic inversion for two cases, one using the conventional P-wave data, where the shear component is estimated, and the second using the multi-component shear data, where it is measured. It is observed that the second case using the measured shear provides improved vertical resolution and lateral continuity of the Marcellus formation members providing potential new insights for Marcellus exploration. The inversion results are used to calculate geomechanical and rock properties of the Marcellus interval. Comparisons are shown for the two inversion cases for the Upper and Lower Marcellus Intervals. Crossplots of Young’s Modulus and Poisson’s Ratio (Brittleness based on Rickman et al - SPE paper)) are compared showing that in general the Lower Marcellus exhibits a lower brittleness than the Upper Marcellus which is better defined in case 2. The depositional presence of high TOC content in the Lower Marcellus shown on gamma ray logs is reflected in low values on density logs. This indicates that it is possible to find these high TOC “sweet spots” on seismic data under the right conditions. Crossplots of rock properties show that these “sweet spots” can be detected, where case 2 with improved density estimates, show better differentiation. The 3D volumes of brittleness and “TOC” are combined to produce a manageable new exploration tool for the Marcellus and other unconventional plays. A common question asked by Geologist, Engineers and Geophysicists involved in unconventional resource plays is “can multi-component 3D seismic help in my onshore exploration effort”. The question has been answered in offshore exploration with numerous examples of reservoir improvements associated with gas clouds and low P-wave impedance contrasts. This paper answers this question for onshore unconventional plays using the Marcellus Shale as an example. It shows that using shear-wave measurements recorded from multi-component 3D seismic, provides better characterization enabling improved vertical resolution and lateral continuity of the Marcellus formation members, superior determination of geomechanical properties such as brittleness, and, good differentiation of density and TOC. This example uses a recent proprietary multi-component 3D recorded simultaneously with a large conventional 3D covering the thickest and highest TOC area in Bedford County, Pennsylvania, where Marcellus drilling activity is highest. The paper shows a comparison of the results obtained from a conventional elastic inversion for two cases, one using the conventional P-wave data, where the shear component is estimated, and the second using the multi-component shear data, where it is measured. It is observed that the second case using the measured shear provides improved vertical resolution and lateral continuity of the Marcellus formation members providing potential new insights for Marcellus exploration. The inversion results are used to calculate geomechanical and rock properties of the Marcellus interval. Comparisons are shown for the two inversion cases for the Upper and Lower Marcellus Intervals. Crossplots of Young’s Modulus and Poisson’s Ratio (Brittleness based on Rickman et al - SPE paper)) are compared showing that in general the Lower Marcellus exhibits a lower brittleness than the Upper Marcellus which is better defined in case 2. The depositional presence of high TOC content in the Lower Marcellus shown on gamma ray logs is reflected in low values on density logs. This indicates that it is possible to find these high TOC “sweet spots” on seismic data under the right conditions. Crossplots of rock properties show that these “sweet spots” can be detected, where case 2 with improved density estimates, show better differentiation. The 3D volumes of brittleness and “TOC” are combined to produce a manageable new exploration tool for the Marcellus and other unconventional plays. Panel_15610 Panel_15610 1:40 PM 2:00 PM

Seismic facies analysis is commonly carried out by classifying seismic waveforms based on their shapes in an interval of interest. It is also carried out by using different seismic attributes, reducing the dimensionality of the input data volumes using Kohonen’s self-organizing maps (SOM), and organizing it into clusters on a 2D map. Such methods are computationally fast and inexpensive. However, they have shortcomings in that there is no definite criteria for selection of a search radius and the learning rate, as these are parameters dependent on the input data. In addition, there is no cost function that is defined and optimized and so usually the method is deficient in providing a measure of confidence that could be assigned to the results. Generative topographic mapping (GTM) has been shown to address the shortcomings of the SOM method and has been suggested as an alternative to it. GTM analysis does a nonlinear dimension reduction in latent space, and provides probabilistic representation of the data. We demonstrate the application of GTM analysis to a 3D seismic volume from central Alberta, Canada, where we focus on the Mannville channels at a depth of 1150 to 1230 m that are filled with interbedded units of shale and sandstone. On the 3D seismic volume, these channels show up at a mean time of 1000 ms plus or minus 50 ms. We first generate different seismic attributes and then using the sweetness, GLCM-energy, GLCM-entropy, GLCM-homogeneity, peak frequency, peak magnitude, coherence and impedance attributes we derive GTM1 and GTM2 outputs. These attributes provided the cluster locations along the two axes in the latent space to be used in the crossplotting that follows. Breaking the 2D latent space into two components allows us to use modern interactive crossplotting tools. While GTM1 shows the definition of the edges very well for the channels, GTM2 exhibits the complete definition of the channels along with their fill in red and blue. We show that the performance of GTM analysis is more encouraging than the simplistic waveform classification or the SOM multiattribute approach. We expect that by using constrained GTM analysis with the help of well log data, the facies patterns we have derived using the unconstrained GTM method used here would be further tightened and made more distinct. Seismic facies analysis is commonly carried out by classifying seismic waveforms based on their shapes in an interval of interest. It is also carried out by using different seismic attributes, reducing the dimensionality of the input data volumes using Kohonen’s self-organizing maps (SOM), and organizing it into clusters on a 2D map. Such methods are computationally fast and inexpensive. However, they have shortcomings in that there is no definite criteria for selection of a search radius and the learning rate, as these are parameters dependent on the input data. In addition, there is no cost function that is defined and optimized and so usually the method is deficient in providing a measure of confidence that could be assigned to the results. Generative topographic mapping (GTM) has been shown to address the shortcomings of the SOM method and has been suggested as an alternative to it. GTM analysis does a nonlinear dimension reduction in latent space, and provides probabilistic representation of the data. We demonstrate the application of GTM analysis to a 3D seismic volume from central Alberta, Canada, where we focus on the Mannville channels at a depth of 1150 to 1230 m that are filled with interbedded units of shale and sandstone. On the 3D seismic volume, these channels show up at a mean time of 1000 ms plus or minus 50 ms. We first generate different seismic attributes and then using the sweetness, GLCM-energy, GLCM-entropy, GLCM-homogeneity, peak frequency, peak magnitude, coherence and impedance attributes we derive GTM1 and GTM2 outputs. These attributes provided the cluster locations along the two axes in the latent space to be used in the crossplotting that follows. Breaking the 2D latent space into two components allows us to use modern interactive crossplotting tools. While GTM1 shows the definition of the edges very well for the channels, GTM2 exhibits the complete definition of the channels along with their fill in red and blue. We show that the performance of GTM analysis is more encouraging than the simplistic waveform classification or the SOM multiattribute approach. We expect that by using constrained GTM analysis with the help of well log data, the facies patterns we have derived using the unconstrained GTM method used here would be further tightened and made more distinct. Panel_15611 Panel_15611 2:00 PM 2:20 PM

The Upper Morrow sandstone reservoir in the western Anadarko Basin is a major oil-producing reservoir. These sandstones have plagued operators and investigators alike, because of their irregular distribution. P-wave studies have been mostly done for characterizing the Morrow sandstones. It is difficult to detect these thin, discontinuous reservoir sandstones using P-wave datasets because of insufficient acoustic impedance contrast between the Morrow sandstone and surrounding shales. But the contrast in rigidity between the Morrow sandstone and surrounding shale causes a strong seismic expression on the shear wave data. This paper shows how S-wave data can help improve the detection of reservoirs with low acoustic impedance contrast. The Reservoir Characterization Project (RCP) at Colorado School of Mines, in conjunction with Whiting Petroleum Corporation, acquired 9C multicomponent seismic survey over a 6.25 square mile area within the Hovey Morrow Unit (HMU) of Postle Field, Oklahoma. The field is undergoing CO2 flood and field rejuvenation is difficult if we are unable to see the reservoir. The primary producing units in the Morrow at Postle Field are Upper Morrow A, A1 and A2 sands. The main reservoir in our study area is the Morrow A sandstone which are at a depth of around 6100 ft and have an average thickness of 30 ft (0-90 ft). The P, SV and SH stacks obtained after processing are interpreted. The Sum of Positive Samples (SPS) amplitude map at Morrow A sandstone peak and the RMS amplitude map at Morrow shale trough are analyzed for all the stacks. The attribute maps are correlated with the Morrow A sandstone gross thickness obtained from well logs. Single attribute analysis shows that SV- and SH-wave attributes give better prediction of Morrow A sandstone thickness compared to P-wave attributes. We find that multi-attribute combination of P, SV and SH data provides better correlation with sandstone thickness as compared to single attribute. Morrow A sandstone thickness map is constructed using a collocated cokriging procedure based on a linear combination of the three attributes obtained from P, SV and SH data. The seismic-guided isopach map is a good way of estimating the sandstone thickness in the study area. The Upper Morrow sandstone reservoir in the western Anadarko Basin is a major oil-producing reservoir. These sandstones have plagued operators and investigators alike, because of their irregular distribution. P-wave studies have been mostly done for characterizing the Morrow sandstones. It is difficult to detect these thin, discontinuous reservoir sandstones using P-wave datasets because of insufficient acoustic impedance contrast between the Morrow sandstone and surrounding shales. But the contrast in rigidity between the Morrow sandstone and surrounding shale causes a strong seismic expression on the shear wave data. This paper shows how S-wave data can help improve the detection of reservoirs with low acoustic impedance contrast. The Reservoir Characterization Project (RCP) at Colorado School of Mines, in conjunction with Whiting Petroleum Corporation, acquired 9C multicomponent seismic survey over a 6.25 square mile area within the Hovey Morrow Unit (HMU) of Postle Field, Oklahoma. The field is undergoing CO₂ flood and field rejuvenation is difficult if we are unable to see the reservoir. The primary producing units in the Morrow at Postle Field are Upper Morrow A, A1 and A2 sands. The main reservoir in our study area is the Morrow A sandstone which are at a depth of around 6100 ft and have an average thickness of 30 ft (0-90 ft). The P, SV and SH stacks obtained after processing are interpreted. The Sum of Positive Samples (SPS) amplitude map at Morrow A sandstone peak and the RMS amplitude map at Morrow shale trough are analyzed for all the stacks. The attribute maps are correlated with the Morrow A sandstone gross thickness obtained from well logs. Single attribute analysis shows that SV- and SH-wave attributes give better prediction of Morrow A sandstone thickness compared to P-wave attributes. We find that multi-attribute combination of P, SV and SH data provides better correlation with sandstone thickness as compared to single attribute. Morrow A sandstone thickness map is constructed using a collocated cokriging procedure based on a linear combination of the three attributes obtained from P, SV and SH data. The seismic-guided isopach map is a good way of estimating the sandstone thickness in the study area. Panel_15609 Panel_15609 2:20 PM 2:40 PM

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One of the important challenges in seismic inversion is to resolve finer structures from band-limited seismic data. Reservoir-oriented full-waveform inversion has the potential to deliver high-resolution quantitative images and is a promising technique to obtain macro-scale physical properties of the subsurface(Ashnashari et al., 2012). Because full-waveform inversion accounts for the entire wavefield, the seismic modelling embedded in the inversion algorithm honors the full physics of wave propagation (Virieux and Operto, 2009). This makes the technique potentially an effective instrument for improving the characterization of complex geological settings (Plessix et al., 2010). Like for most geophysical application, prior information such as data collected in wells is available and should be used to improve the result. For this purpose we propose a new strategy for including geological prior knowledge in full-waveform inversion, which will ensure an even higher resolution in the final images. This new scheme does not constrain the inversion but uses blocky models drawn from the prior distribution as a starting point for the inversion. After an unconstrained inversion, the non-blocky result is re-interpreted in terms of the prior model. This can be seen as a Bayesian update in iterative non-linear inversion , this process is repeated after every iteration. This updated blocky model will be used as a starting model for the next iteration. This leads to a guided, nonlinear inversion process, where a geological scenario is proposed between two linear iteration steps. Given the prior probabilities and covariances, we are able to interpret the presence or absence of thin layers that otherwise cannot be detected using only band-limited seismic data. This scheme is demonstrated on a high-resolution synthetic model based on the Book cliff outcrop in Utah(USA). One of the important challenges in seismic inversion is to resolve finer structures from band-limited seismic data. Reservoir-oriented full-waveform inversion has the potential to deliver high-resolution quantitative images and is a promising technique to obtain macro-scale physical properties of the subsurface(Ashnashari et al., 2012). Because full-waveform inversion accounts for the entire wavefield, the seismic modelling embedded in the inversion algorithm honors the full physics of wave propagation (Virieux and Operto, 2009). This makes the technique potentially an effective instrument for improving the characterization of complex geological settings (Plessix et al., 2010). Like for most geophysical application, prior information such as data collected in wells is available and should be used to improve the result. For this purpose we propose a new strategy for including geological prior knowledge in full-waveform inversion, which will ensure an even higher resolution in the final images. This new scheme does not constrain the inversion but uses blocky models drawn from the prior distribution as a starting point for the inversion. After an unconstrained inversion, the non-blocky result is re-interpreted in terms of the prior model. This can be seen as a Bayesian update in iterative non-linear inversion , this process is repeated after every iteration. This updated blocky model will be used as a starting model for the next iteration. This leads to a guided, nonlinear inversion process, where a geological scenario is proposed between two linear iteration steps. Given the prior probabilities and covariances, we are able to interpret the presence or absence of thin layers that otherwise cannot be detected using only band-limited seismic data. This scheme is demonstrated on a high-resolution synthetic model based on the Book cliff outcrop in Utah(USA). Panel_15608 Panel_15608 3:25 PM 3:45 PM

Several oil and gas domains raise 3D seismic imaging challenges or are only imaged with 2D seismic lines. In both cases the shape and the connectivity of faults is subject to uncertainties which may be consequential for the determination of migration paths, trap geometry and reservoir compartmentalization. Stochastic fault network simulation aims at generating a set of 3D structural models honoring prior structural concepts and conditioned by interpretations made from wells and seismic data. This set of models aims at sampling the uncertainty space related to the fault network geometry and connectivity (topology is variable from one realization to the next and emerges from the simulation process). We apply this stochastic approach to a highly-uncertain and complex fault network at reservoir scale. The used dataset is composed of several wells and 3D seismic data that poorly image the reservoir. We show how the tectonic history and the structural style can be conveyed to a stochastic fault modeling system in order to ensure the simulation of consistent 3D fault networks. We also discuss the strategy to generate suitable spatial interpretations from 3D seismic data. We then use statistical analyzes to evaluate the uncertainty about the number of faults and the number of compartments in the reservoir. Several oil and gas domains raise 3D seismic imaging challenges or are only imaged with 2D seismic lines. In both cases the shape and the connectivity of faults is subject to uncertainties which may be consequential for the determination of migration paths, trap geometry and reservoir compartmentalization. Stochastic fault network simulation aims at generating a set of 3D structural models honoring prior structural concepts and conditioned by interpretations made from wells and seismic data. This set of models aims at sampling the uncertainty space related to the fault network geometry and connectivity (topology is variable from one realization to the next and emerges from the simulation process). We apply this stochastic approach to a highly-uncertain and complex fault network at reservoir scale. The used dataset is composed of several wells and 3D seismic data that poorly image the reservoir. We show how the tectonic history and the structural style can be conveyed to a stochastic fault modeling system in order to ensure the simulation of consistent 3D fault networks. We also discuss the strategy to generate suitable spatial interpretations from 3D seismic data. We then use statistical analyzes to evaluate the uncertainty about the number of faults and the number of compartments in the reservoir. Panel_15607 Panel_15607 3:45 PM 4:05 PM

Global seismic interpretation solutions are changing trends in seismic interpretation because they allow auto-tracking of hundreds of seismic reflectors. A method for generating these horizons that utilizes an algorithm based on dip- and azimuth data is presented. Previously, interpreter input to the workflow was limited but with evolving technology, interpreters are now able to correlate polygonal regions bounded by horizons and faults, channels or mounds, manually. The result is more robust and minimizes uncertainties. A regional 2D line was selected to demonstrate the workflow and results. The line is located offshore Tanzania, which has seen increased interest in exploration activities in recent years. The setting is a combination of complex structural and stratigraphic elements and includes several channelized sections at different stratigraphic levels. These features make it ideal to demonstrate the workflow. By utilizing thousands of auto-picked events and adding constraints in an iterative manner, we were able to produce more reliable Wheeler (flattened) diagrams. The structural and Wheeler domains were then used to pick boundaries for packages where changes in stacking patterns or amplitude character were observed. “Regions” were then correlated manually to obtain time-equivalent RGT (Relative Geologic Time) lines, or iso-time lines, across the regional 2D line. Global seismic interpretation solutions are changing trends in seismic interpretation because they allow auto-tracking of hundreds of seismic reflectors. A method for generating these horizons that utilizes an algorithm based on dip- and azimuth data is presented. Previously, interpreter input to the workflow was limited but with evolving technology, interpreters are now able to correlate polygonal regions bounded by horizons and faults, channels or mounds, manually. The result is more robust and minimizes uncertainties. A regional 2D line was selected to demonstrate the workflow and results. The line is located offshore Tanzania, which has seen increased interest in exploration activities in recent years. The setting is a combination of complex structural and stratigraphic elements and includes several channelized sections at different stratigraphic levels. These features make it ideal to demonstrate the workflow. By utilizing thousands of auto-picked events and adding constraints in an iterative manner, we were able to produce more reliable Wheeler (flattened) diagrams. The structural and Wheeler domains were then used to pick boundaries for packages where changes in stacking patterns or amplitude character were observed. “Regions” were then correlated manually to obtain time-equivalent RGT (Relative Geologic Time) lines, or iso-time lines, across the regional 2D line. Panel_15605 Panel_15605 4:05 PM 4:25 PM

As petroleum exploration has gravitated towards deep, poorly imaged often sub-salt reservoirs, it has become critical to develop new approaches that can be used to improve quality of seismic image and pre-drill pressure predictions. Seismic imaging usually is based on tomography to derive a velocity model. For difficult area, such as subsalt where tomography cannot be used reliably, subsalt velocity scan or HBI (horizon based interpolation) become very useful. This presentation introduces new geologically constrained pressure and velocity workflows that integrate basin modeling, tomography, geomechanics, and petrophysics. They honor stratigraphy, depositional environment and account for the evolution of rock properties due to burial or changing pressure / temperature conditions, diagenesis, etc. Our workflows consist of several steps that include basin modeling, tomography, petrophysical and geomechanical data analysis and integration, building hybrid velocity models, and pre-stack depth migration. The process of basin model building and subsequent depth imaging starts in the shallow section, where the image is typically better and iteratively propagates downwards. After each iteration a hybrid velocity model is built using velocities from tomography and velocities from basin modeling. Here are two examples of hybrid model building: (1) When the measure of gather flatness for common image gathers satisfies a predefined threshold error level, the velocity values for the region in the tomography velocity model are used; when the measure of gather flatness does not satisfy the predefined threshold error level, the velocity values for the region in the tomography velocity model are replaced with the corresponding velocity values for the region in the basin modeling derived velocity model. The hybrid model is then smoothed before being used in pre-stack depth migration (2) Use of velocities from tomography in the shallow hydrostatic pore pressure section and velocities from basin modeling in the abnormal pore pressure (below hydrostatic) section, where tomography typically looses fidelity. Selected case studies indicate that in addition to improved pre-drill pressure predictions new workflows result in improved image and ability to interpret deep subsalt section. As petroleum exploration has gravitated towards deep, poorly imaged often sub-salt reservoirs, it has become critical to develop new approaches that can be used to improve quality of seismic image and pre-drill pressure predictions. Seismic imaging usually is based on tomography to derive a velocity model. For difficult area, such as subsalt where tomography cannot be used reliably, subsalt velocity scan or HBI (horizon based interpolation) become very useful. This presentation introduces new geologically constrained pressure and velocity workflows that integrate basin modeling, tomography, geomechanics, and petrophysics. They honor stratigraphy, depositional environment and account for the evolution of rock properties due to burial or changing pressure / temperature conditions, diagenesis, etc. Our workflows consist of several steps that include basin modeling, tomography, petrophysical and geomechanical data analysis and integration, building hybrid velocity models, and pre-stack depth migration. The process of basin model building and subsequent depth imaging starts in the shallow section, where the image is typically better and iteratively propagates downwards. After each iteration a hybrid velocity model is built using velocities from tomography and velocities from basin modeling. Here are two examples of hybrid model building: (1) When the measure of gather flatness for common image gathers satisfies a predefined threshold error level, the velocity values for the region in the tomography velocity model are used; when the measure of gather flatness does not satisfy the predefined threshold error level, the velocity values for the region in the tomography velocity model are replaced with the corresponding velocity values for the region in the basin modeling derived velocity model. The hybrid model is then smoothed before being used in pre-stack depth migration (2) Use of velocities from tomography in the shallow hydrostatic pore pressure section and velocities from basin modeling in the abnormal pore pressure (below hydrostatic) section, where tomography typically looses fidelity. Selected case studies indicate that in addition to improved pre-drill pressure predictions new workflows result in improved image and ability to interpret deep subsalt section. Panel_15613 Panel_15613 4:25 PM 4:45 PM

Pre-stack time migration (PSTM) has pitfalls in processing seismic data which causes artificial features on seismic images and might mislead the structural interpretation. First, fault shadows give rise to a second (artificial) discontinuity coherence images computed from PSTM data. Second, velocity pull-up and push-down caused by the lateral changes in the overburden such as carbonate buildups and incised valleys will give rise to erroneous curvature anomalies in PSTM data. Besides, PSTM data may be poorly focused in complex structures. Fault terminations of reflectors may be misaligned, giving rise to “wormy” coherence anomalies. Channels and other stratigraphic features may be diffused, making them hard to interpret. To remove the above pitfalls caused by PSTM, pre-stack depth migration (PSDM), which assumes that seismic waves are propagated in straight rays, is necessary in the presence of strong lateral velocity variation to avoid these artifacts. The more accurate velocity model established by PSDM better images complex structures. The seismic data from the Bohai Bay Basin in China are separately processed by PSTM as well as PSDM, combining with seismic attributes, to compare the seismic imaging quality. Several sub-fault splays artifacts in coherence generate the fault-shadow zones under dipping main faults in PSTM data, but disappear in PSDM data. The curvature anomalies related to the lateral variations may be misinterpreted as real structures in PSTM data, which are removed in precise velocity PSDM data. Therefore, In the presence of strong lateral variations in velocity, PSDM is better for interpreting complex structures comparing PSTM which fails to properly image the subsurface. Pre-stack time migration (PSTM) has pitfalls in processing seismic data which causes artificial features on seismic images and might mislead the structural interpretation. First, fault shadows give rise to a second (artificial) discontinuity coherence images computed from PSTM data. Second, velocity pull-up and push-down caused by the lateral changes in the overburden such as carbonate buildups and incised valleys will give rise to erroneous curvature anomalies in PSTM data. Besides, PSTM data may be poorly focused in complex structures. Fault terminations of reflectors may be misaligned, giving rise to “wormy” coherence anomalies. Channels and other stratigraphic features may be diffused, making them hard to interpret. To remove the above pitfalls caused by PSTM, pre-stack depth migration (PSDM), which assumes that seismic waves are propagated in straight rays, is necessary in the presence of strong lateral velocity variation to avoid these artifacts. The more accurate velocity model established by PSDM better images complex structures. The seismic data from the Bohai Bay Basin in China are separately processed by PSTM as well as PSDM, combining with seismic attributes, to compare the seismic imaging quality. Several sub-fault splays artifacts in coherence generate the fault-shadow zones under dipping main faults in PSTM data, but disappear in PSDM data. The curvature anomalies related to the lateral variations may be misinterpreted as real structures in PSTM data, which are removed in precise velocity PSDM data. Therefore, In the presence of strong lateral variations in velocity, PSDM is better for interpreting complex structures comparing PSTM which fails to properly image the subsurface. Panel_15606 Panel_15606 4:45 PM 5:05 PM

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Panel_15772 Panel_15772 1:15 PM 12:00 AM

Deep-water channel compartmentalization and heterogeneity pose significant technical and business challenges to reservoir characterization and development. Some channel systems are better connected than expected, whereas others are more compartmentalized. A detailed understanding of stratigraphic architecture is fundamentally important to reduce connectivity uncertainty. We integrate an exceptional high-resolution seismic-reflection dataset (dominant frequency 40 Hz) from offshore West Africa with well-log, core, dynamic, and analog data to investigate stratigraphic controls on reservoir heterogeneity and compartmentalization of the Miocene ‘L’ deepwater channel system. Detailed analysis of the ‘L’ channel system indicates that it comprises terraces of remnant, isolated channel elements and possible down-dip heterogeneity of channel fill. The stratigraphic evolution was dominated by the development of at least three large-scale (>50 ms TWTT relief) composite erosional surfaces. Each erosional surface cut deeper than the last, thereby isolating terraces of high-quality sand at multiple stratigraphic levels. These terraces are remnants of channel elements that were deposited during an earlier phase of the channel system. Therefore, the development of large-scale erosional surfaces is fundamentally important to reservoir compartmentalization. We interpret these surfaces to be a diachronous expression of predominantly incision, but also multi-phase channel element cutting, filling, and stacking. This evolution has been interpreted to represent a combination of changing sea level, evolving sediment source characteristics, and the dynamic geomorphology of tectonically active continental margins. We place our interpretations in an architectural hierarchy, and consider the impact of reservoir compartmentalization and heterogeneity on fluid flow behavior during hydrocarbon production. These interpretations inform the modeling and prediction of 3D heterogeneity of deep-water reservoirs and illustrate the importance of detailed characterization at a very-fine scale in order to understand reservoir connectivity. Deep-water channel compartmentalization and heterogeneity pose significant technical and business challenges to reservoir characterization and development. Some channel systems are better connected than expected, whereas others are more compartmentalized. A detailed understanding of stratigraphic architecture is fundamentally important to reduce connectivity uncertainty. We integrate an exceptional high-resolution seismic-reflection dataset (dominant frequency 40 Hz) from offshore West Africa with well-log, core, dynamic, and analog data to investigate stratigraphic controls on reservoir heterogeneity and compartmentalization of the Miocene ‘L’ deepwater channel system. Detailed analysis of the ‘L’ channel system indicates that it comprises terraces of remnant, isolated channel elements and possible down-dip heterogeneity of channel fill. The stratigraphic evolution was dominated by the development of at least three large-scale (>50 ms TWTT relief) composite erosional surfaces. Each erosional surface cut deeper than the last, thereby isolating terraces of high-quality sand at multiple stratigraphic levels. These terraces are remnants of channel elements that were deposited during an earlier phase of the channel system. Therefore, the development of large-scale erosional surfaces is fundamentally important to reservoir compartmentalization. We interpret these surfaces to be a diachronous expression of predominantly incision, but also multi-phase channel element cutting, filling, and stacking. This evolution has been interpreted to represent a combination of changing sea level, evolving sediment source characteristics, and the dynamic geomorphology of tectonically active continental margins. We place our interpretations in an architectural hierarchy, and consider the impact of reservoir compartmentalization and heterogeneity on fluid flow behavior during hydrocarbon production. These interpretations inform the modeling and prediction of 3D heterogeneity of deep-water reservoirs and illustrate the importance of detailed characterization at a very-fine scale in order to understand reservoir connectivity. Panel_15194 Panel_15194 1:20 PM 1:40 PM

Over the past two decades sandstone intrusions have been increasingly recognized as an important component of the deepwater Paleogene petroleum province of the North Sea where entire oil fields are hosted in intrusive traps. In several of the largest developments coming on stream in the UK in the next decade, sandstone intrusions are a critical part of the reservoir volume, geometry and connectivity, highlighting the economical importance of these structures to the petroleum industry. Although the importance of large-scale sandstone intrusions have been recognised for many years in the North Sea, examples from around the world have only started emerging in the past few years, driven primarily by the emergence of high-quality 3D seismic datasets in frontier deepwater regions including Angola, Nigeria, Uruguay and New Zealand. Large-scale sandstone intrusions recognized in seismic data are typically between 50-300 m tall, 200-2000m wide and up to 3-4 km long with limb thicknesses of some 5-100 m. Resulting volumes range from < 0.1 km3 to several km3 for clusters of visibly connected intrusions. This presentation will showcase well documented examples of sand injectite oil fields as well as frontier specimens, highlighting the recognition criteria and their importance to regional and local exploration. We will discuss their interpretation, based on seismic stratigraphic criteria, enabling the distinction of classical lowstand fans and channels from mass transport complexes and their partly remobilised equivalents from fully intrusive sandstones. The importance for exploration and development and production will be demonstrated by means of production data. Sandstone intrusions form thick high-quality reservoirs in unusual basinal locations and violate seals by inserting sub-vertical permeability (several Darcy) conduits that may crosscut hundreds of metres of poorly permeable mudstones. The recognition of deepwater massive sandstones of intrusive origin therefore poses important challenges to deepwater exploration traditionally driven by classic seismic stratigraphic approaches. Over the past two decades sandstone intrusions have been increasingly recognized as an important component of the deepwater Paleogene petroleum province of the North Sea where entire oil fields are hosted in intrusive traps. In several of the largest developments coming on stream in the UK in the next decade, sandstone intrusions are a critical part of the reservoir volume, geometry and connectivity, highlighting the economical importance of these structures to the petroleum industry. Although the importance of large-scale sandstone intrusions have been recognised for many years in the North Sea, examples from around the world have only started emerging in the past few years, driven primarily by the emergence of high-quality 3D seismic datasets in frontier deepwater regions including Angola, Nigeria, Uruguay and New Zealand. Large-scale sandstone intrusions recognized in seismic data are typically between 50-300 m tall, 200-2000m wide and up to 3-4 km long with limb thicknesses of some 5-100 m. Resulting volumes range from < 0.1 km3 to several km3 for clusters of visibly connected intrusions. This presentation will showcase well documented examples of sand injectite oil fields as well as frontier specimens, highlighting the recognition criteria and their importance to regional and local exploration. We will discuss their interpretation, based on seismic stratigraphic criteria, enabling the distinction of classical lowstand fans and channels from mass transport complexes and their partly remobilised equivalents from fully intrusive sandstones. The importance for exploration and development and production will be demonstrated by means of production data. Sandstone intrusions form thick high-quality reservoirs in unusual basinal locations and violate seals by inserting sub-vertical permeability (several Darcy) conduits that may crosscut hundreds of metres of poorly permeable mudstones. The recognition of deepwater massive sandstones of intrusive origin therefore poses important challenges to deepwater exploration traditionally driven by classic seismic stratigraphic approaches. Panel_15189 Panel_15189 1:40 PM 2:00 PM

The connectivity and facies heterogeneity of low permeability, terminal deep-water lobes are important uncertainties in reservoir characterization and development. Deep-water lobes have been conceptualized as basinwide, sheet-like deposits. However, recent work has shown more complex 3D architecture and spatial variability of petrophysical properties, which can have significant impact on reservoir performance. We use high-resolution seismic-reflection data (dominant frequency ~40 Hz) from the shallow subsurface of the Niger Delta continental slope to illustrate the stratigraphic architecture and facies variability of a deep-water lobe system. The interval of interest is a package of high-amplitude seismic reflections that is lobate in plan view and externally mounded in cross section. This interval comprises at least three sub-packages of continuous, single- or multi-cycle seismic reflections, which locally exhibit bidirectional downlap and compensational stacking. Reflections bounding the uppermost sub-package represent channel avulsion, compensation and modification of initial deposits, unconfined deposition at the channel mouth, and downstream channel bifurcation. We place our interpretations within an architectural hierarchy and consider the impact of depositional heterogeneity on fluid flow behavior during hydrocarbon production. These interpretations inform the modeling and prediction of 3D heterogeneity of deep-water lobes and illustrate the importance of detailed characterization in order to understand reservoir connectivity and quality. The connectivity and facies heterogeneity of low permeability, terminal deep-water lobes are important uncertainties in reservoir characterization and development. Deep-water lobes have been conceptualized as basinwide, sheet-like deposits. However, recent work has shown more complex 3D architecture and spatial variability of petrophysical properties, which can have significant impact on reservoir performance. We use high-resolution seismic-reflection data (dominant frequency ~40 Hz) from the shallow subsurface of the Niger Delta continental slope to illustrate the stratigraphic architecture and facies variability of a deep-water lobe system. The interval of interest is a package of high-amplitude seismic reflections that is lobate in plan view and externally mounded in cross section. This interval comprises at least three sub-packages of continuous, single- or multi-cycle seismic reflections, which locally exhibit bidirectional downlap and compensational stacking. Reflections bounding the uppermost sub-package represent channel avulsion, compensation and modification of initial deposits, unconfined deposition at the channel mouth, and downstream channel bifurcation. We place our interpretations within an architectural hierarchy and consider the impact of depositional heterogeneity on fluid flow behavior during hydrocarbon production. These interpretations inform the modeling and prediction of 3D heterogeneity of deep-water lobes and illustrate the importance of detailed characterization in order to understand reservoir connectivity and quality. Panel_15193 Panel_15193 2:00 PM 2:20 PM

Turbiditic systems are characterized by a great variability in size, geometry, facies, and stacking patterns. The development of depositional models at the basin scale is essential to understand this variability. Models require an accurate knowledge of the paleocurrent directions within the turbiditic systems. Traditionally, sedimentological current indicators (flute marks, ripple marks, etc.) are used to obtain paleocurrent directions, but these are not always present in outcrop sections and are virtually absent from drill cores. This limitation raises the need to identify an alternative, objective method to define paleocurrent directions in turbiditic successions. The anisotropy of magnetic susceptibility (AMS) is a useful tool to estimate paleocurrents in sedimentary rocks (e.g. turbiditic, fluvial, tide-dominated deltaic and estuarine environments). This method is based on the fact that a current is able to orient para- and ferromagnetic grains and minerals. The AMS ellipsoid often reflects the orientation imparted by the current to such grains. We experiment this method, in concert with classic sedimentological analyses, in two well-exposed Miocene turbiditic systems cropping out in the Northern Apennines (Italy): the Castagnola turbidite system (Tertiary Piedmont Basin) and the Marnoso Arenacea Formation (Northern Apennines foredeep). They are both characterized by well exposed strathigraphic sections and by the presence of evident sedimentological indicators of paleocurrent at the base of the beds, that have been used to validate the AMS measurements. As we were interested to calibrate this method and to determine which sediment composition and texture (grain size and sedimentary structures) work best for the application of the AMS methodology, numerous turbiditic sandstone beds have been sampled (nearly 900 samples collected) into different depositional intervals (e.g, fine- to medium-grained massive sands, fine- to medium-grained parallel-laminated sands and fine-grained cross-laminated sands). AMS fabrics have been compared to sedimentological indicators of paleocurrent direction at the base of turbidite beds; a good agreement between paleocurrents from flute casts and AMS measurements has been observed, even if a relatively small but consistent offset of ~15–20° seems to be present. Nonetheless, these data confirm the substantial validity of the AMS method as a tool to estimate flow directions in absence of sedimentological indicator. Turbiditic systems are characterized by a great variability in size, geometry, facies, and stacking patterns. The development of depositional models at the basin scale is essential to understand this variability. Models require an accurate knowledge of the paleocurrent directions within the turbiditic systems. Traditionally, sedimentological current indicators (flute marks, ripple marks, etc.) are used to obtain paleocurrent directions, but these are not always present in outcrop sections and are virtually absent from drill cores. This limitation raises the need to identify an alternative, objective method to define paleocurrent directions in turbiditic successions. The anisotropy of magnetic susceptibility (AMS) is a useful tool to estimate paleocurrents in sedimentary rocks (e.g. turbiditic, fluvial, tide-dominated deltaic and estuarine environments). This method is based on the fact that a current is able to orient para- and ferromagnetic grains and minerals. The AMS ellipsoid often reflects the orientation imparted by the current to such grains. We experiment this method, in concert with classic sedimentological analyses, in two well-exposed Miocene turbiditic systems cropping out in the Northern Apennines (Italy): the Castagnola turbidite system (Tertiary Piedmont Basin) and the Marnoso Arenacea Formation (Northern Apennines foredeep). They are both characterized by well exposed strathigraphic sections and by the presence of evident sedimentological indicators of paleocurrent at the base of the beds, that have been used to validate the AMS measurements. As we were interested to calibrate this method and to determine which sediment composition and texture (grain size and sedimentary structures) work best for the application of the AMS methodology, numerous turbiditic sandstone beds have been sampled (nearly 900 samples collected) into different depositional intervals (e.g, fine- to medium-grained massive sands, fine- to medium-grained parallel-laminated sands and fine-grained cross-laminated sands). AMS fabrics have been compared to sedimentological indicators of paleocurrent direction at the base of turbidite beds; a good agreement between paleocurrents from flute casts and AMS measurements has been observed, even if a relatively small but consistent offset of ~15–20° seems to be present. Nonetheless, these data confirm the substantial validity of the AMS method as a tool to estimate flow directions in absence of sedimentological indicator. Panel_15191 Panel_15191 2:20 PM 2:40 PM

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Documenting the range of sedimentary facies associations in the different sub-environments of submarine lobe deposits is important in the accurate prediction of reservoir quality and connectivity in subsurface datasets. Lobe axis (thick bedded structureless to planar laminated sandstone) and off-axis (structured medium bedded sandstone) facies associations are somewhat predictable but lobe fringe facies associations can vary between and within different deep-water systems, such that the length-scales of facies transitions from lobe axes to fringes are poorly understood. This means that reservoir cut-off in fringe settings is difficult to predict. The integration of extensive outcrop data and newly acquired core data from behind-outcrops research wells of Fan 4, Skoorstenberg Formation, permit the range of facies associations and rate of facies transitions in lobes and lobe complexes to be quantified within a well constrained palaeogeographic context. Outcrop and core sections were logged bed-by-bed, integrated with palaeocurrent measurements and correlated over a 1050 km2 study area with good 3D data distribution. Fan 4 is interpreted as a lowstand systems tract lobe complex set, comprises two lobe complexes separated by ~70 cm of hemipelagic claystone and stacked in a compensational pattern. Statistical analysis was performed to establish unbiased facies trends over the fan sub-environments. Lobe fringe associations can be i) thick bedded structureless to planar laminated sandstones that show pinching and swelling and are associated with underlying debrites, ii) current ripple laminated sandstones and siltstones, or iii) prone to argillaceous and clast-rich linked debrites depending on confinement and position in the lobe complex. Commonly, frontal fringes are more concentrated in linked debrites and transition from thick-bedded sandstones over length-scales of 1-2 km, whereas lateral fringes tend to be current ripple-laminated sandstones and siltstones that transition from thick-bedded lobe axis sandstones over several kilometres. A stratigraphic trend is noted, with fringes of earlier lobes being more prone to clast-rich linked debrites. This trend is interpreted to reflect the development of slope degradation and entrainment of slope mud into flows during the initiation of a lowstand systems tract. Constraining geometries, stacking patterns, facies trends and distributions in lobe complexes is critical to reservoir evaluation and prediction. Documenting the range of sedimentary facies associations in the different sub-environments of submarine lobe deposits is important in the accurate prediction of reservoir quality and connectivity in subsurface datasets. Lobe axis (thick bedded structureless to planar laminated sandstone) and off-axis (structured medium bedded sandstone) facies associations are somewhat predictable but lobe fringe facies associations can vary between and within different deep-water systems, such that the length-scales of facies transitions from lobe axes to fringes are poorly understood. This means that reservoir cut-off in fringe settings is difficult to predict. The integration of extensive outcrop data and newly acquired core data from behind-outcrops research wells of Fan 4, Skoorstenberg Formation, permit the range of facies associations and rate of facies transitions in lobes and lobe complexes to be quantified within a well constrained palaeogeographic context. Outcrop and core sections were logged bed-by-bed, integrated with palaeocurrent measurements and correlated over a 1050 km² study area with good 3D data distribution. Fan 4 is interpreted as a lowstand systems tract lobe complex set, comprises two lobe complexes separated by ~70 cm of hemipelagic claystone and stacked in a compensational pattern. Statistical analysis was performed to establish unbiased facies trends over the fan sub-environments. Lobe fringe associations can be i) thick bedded structureless to planar laminated sandstones that show pinching and swelling and are associated with underlying debrites, ii) current ripple laminated sandstones and siltstones, or iii) prone to argillaceous and clast-rich linked debrites depending on confinement and position in the lobe complex. Commonly, frontal fringes are more concentrated in linked debrites and transition from thick-bedded sandstones over length-scales of 1-2 km, whereas lateral fringes tend to be current ripple-laminated sandstones and siltstones that transition from thick-bedded lobe axis sandstones over several kilometres. A stratigraphic trend is noted, with fringes of earlier lobes being more prone to clast-rich linked debrites. This trend is interpreted to reflect the development of slope degradation and entrainment of slope mud into flows during the initiation of a lowstand systems tract. Constraining geometries, stacking patterns, facies trends and distributions in lobe complexes is critical to reservoir evaluation and prediction. Panel_15190 Panel_15190 3:25 PM 3:45 PM

Numerous studies have pointed at the significance of relay ramps delivering sand to active rift basins during the climax stage. In marine rift systems, relay ramps can provide a conduit between a subaerially exposed highland in the footwall down into a deep-water hanging wall basin. Due to their isolated nature, deep subaqueous rift basins are prone to anoxia and deposition of organic-rich rocks that may generate oil and gas. A potential reservoir close to the hydrocarbon kitchen minimizes migration risk. Outcrop examples of deep marine rift deposits are rare, and interference between sediment influx through relay ramps and from fault scarps in a rift setting as commonly can be inferred from seismic studies is scarcely documented in outcrop. In the Wollaston Forland extensional basin (East Greenland), coarse clastic submarine gravity flows were delivered from the subaerially exposed footwall and deposited in a c. 1 km deep, 20 km wide and 100 km long depocentre in the hanging wall during the rift climax phase. Proximally, the stratigraphy is characterized by thick, uniform but disorganized successions of gravels and breccias containing huge rock-fall slabs. These deposits signify slope aprons and gravel-rich fans sourced from the immediate footwall. Locally, the apron and fan beds interfinger with more sand-prone facies that consist of fine- to medium-grained turbidites and matrix-rich event beds. These facies reflect deposition in a sand-rich submarine fan environment; the abundance of reworked mud and carbonaceous material suggests that it was sourced from a more mature delta system. The interfingering of coarse gravity flow deposits and the sandy fan deposits is only observed south-east of a prominent south-facing relay ramp. The invoked presence of a delta delivering sand to the basin at a relay ramp is consistent with conceptual models. The studied bedforms display a complex architecture in outcrop, comprising scours, heaps and lobe pinch-outs. Most of these features occur on a scale of meters to tens of meters, and are thus below seismic resolution. On seismic data from similar basins such wedges are typically characterized as poorly reflective and chaotic. Given the range of grain sizes that occur together, the complex stratal architecture has a profound influence on reservoir performance. This study provides an overview of the heterogeneity that can be expected in a siliciclastic reservoir deposited in a deep subaqueous setting during rift climax. Numerous studies have pointed at the significance of relay ramps delivering sand to active rift basins during the climax stage. In marine rift systems, relay ramps can provide a conduit between a subaerially exposed highland in the footwall down into a deep-water hanging wall basin. Due to their isolated nature, deep subaqueous rift basins are prone to anoxia and deposition of organic-rich rocks that may generate oil and gas. A potential reservoir close to the hydrocarbon kitchen minimizes migration risk. Outcrop examples of deep marine rift deposits are rare, and interference between sediment influx through relay ramps and from fault scarps in a rift setting as commonly can be inferred from seismic studies is scarcely documented in outcrop. In the Wollaston Forland extensional basin (East Greenland), coarse clastic submarine gravity flows were delivered from the subaerially exposed footwall and deposited in a c. 1 km deep, 20 km wide and 100 km long depocentre in the hanging wall during the rift climax phase. Proximally, the stratigraphy is characterized by thick, uniform but disorganized successions of gravels and breccias containing huge rock-fall slabs. These deposits signify slope aprons and gravel-rich fans sourced from the immediate footwall. Locally, the apron and fan beds interfinger with more sand-prone facies that consist of fine- to medium-grained turbidites and matrix-rich event beds. These facies reflect deposition in a sand-rich submarine fan environment; the abundance of reworked mud and carbonaceous material suggests that it was sourced from a more mature delta system. The interfingering of coarse gravity flow deposits and the sandy fan deposits is only observed south-east of a prominent south-facing relay ramp. The invoked presence of a delta delivering sand to the basin at a relay ramp is consistent with conceptual models. The studied bedforms display a complex architecture in outcrop, comprising scours, heaps and lobe pinch-outs. Most of these features occur on a scale of meters to tens of meters, and are thus below seismic resolution. On seismic data from similar basins such wedges are typically characterized as poorly reflective and chaotic. Given the range of grain sizes that occur together, the complex stratal architecture has a profound influence on reservoir performance. This study provides an overview of the heterogeneity that can be expected in a siliciclastic reservoir deposited in a deep subaqueous setting during rift climax. Panel_15188 Panel_15188 3:45 PM 4:05 PM

The slope-basin transition typically includes the channel-lobe transition zone (CLTZ), which in deep-water turbidite system separates slope channels from more basinward depositional lobes. Although the seismic imaging of modern CLTZs has much improved, it still provides only limited insight into the lithological make up, stratigraphic architecture and stratigraphic evolution of this important zone of stratigraphic and oceanographic transition. In this study, a well exposed ~250 m-thick by 1200 m-wide outcrop separates basin floor “sheets” of the uppermost Kaza Group from leveed slope channels of the Isaac Formation, and therein provides an excellent opportunity to analyze the spatial and temporal development of a well-constrained CLTZ. Here the transition zone comprises a complex assemblage of small and large scours, proximal and distal distributary channels, terminal splays, and fine-grained sheets, and at its top, a leveed slope channel. Mass-wasting deposits (debrites and slides), erosional channels, crevasse splays and hydraulic-jump bars are also documented. Unique to the transition zone are scours, whose fills show little vertical or lateral lithological change. Small scours are typically 1-4 m deep and extend laterally for 10- >600 m, and are generally filled with thick- to medium-bedded, structureless or planar-laminated, very coarse- to coarse-grained sandstone. Less commonly, small scours are filled with thin-bedded turbidites, debrites, granule conglomerate, or mudstone-clast breccia. A rare large scour is recognized. It is up to 32 m deep by >600 wide, and is divided in two parts: a lower unit with several conglomerate- and sandstone-rich, small scour-fills that locally are amalgamated; and an upper unit composed of multiple sandstone-filled small scours typically encased in thin-bedded turbidites. Detailed analyses along the Kaza-Isaac transition zone reveal two different architectural assemblages that stack vertically: a lower unit of a large scour that overlies a succession dominated by distributary channel-fills, and an upper unit of alternating small scours and basin-floor elements (e.g. distributary channels and terminal splays). Such changes in architectural styles coincide with changes in sediment supply, namely sediment volume and caliber, which are interpreted to be linked with major changes in relative sea level. This large-scale architecture may be comparable to other turbidite systems and has implications for reservoir connectivity. The slope-basin transition typically includes the channel-lobe transition zone (CLTZ), which in deep-water turbidite system separates slope channels from more basinward depositional lobes. Although the seismic imaging of modern CLTZs has much improved, it still provides only limited insight into the lithological make up, stratigraphic architecture and stratigraphic evolution of this important zone of stratigraphic and oceanographic transition. In this study, a well exposed ~250 m-thick by 1200 m-wide outcrop separates basin floor “sheets” of the uppermost Kaza Group from leveed slope channels of the Isaac Formation, and therein provides an excellent opportunity to analyze the spatial and temporal development of a well-constrained CLTZ. Here the transition zone comprises a complex assemblage of small and large scours, proximal and distal distributary channels, terminal splays, and fine-grained sheets, and at its top, a leveed slope channel. Mass-wasting deposits (debrites and slides), erosional channels, crevasse splays and hydraulic-jump bars are also documented. Unique to the transition zone are scours, whose fills show little vertical or lateral lithological change. Small scours are typically 1-4 m deep and extend laterally for 10- >600 m, and are generally filled with thick- to medium-bedded, structureless or planar-laminated, very coarse- to coarse-grained sandstone. Less commonly, small scours are filled with thin-bedded turbidites, debrites, granule conglomerate, or mudstone-clast breccia. A rare large scour is recognized. It is up to 32 m deep by >600 wide, and is divided in two parts: a lower unit with several conglomerate- and sandstone-rich, small scour-fills that locally are amalgamated; and an upper unit composed of multiple sandstone-filled small scours typically encased in thin-bedded turbidites. Detailed analyses along the Kaza-Isaac transition zone reveal two different architectural assemblages that stack vertically: a lower unit of a large scour that overlies a succession dominated by distributary channel-fills, and an upper unit of alternating small scours and basin-floor elements (e.g. distributary channels and terminal splays). Such changes in architectural styles coincide with changes in sediment supply, namely sediment volume and caliber, which are interpreted to be linked with major changes in relative sea level. This large-scale architecture may be comparable to other turbidite systems and has implications for reservoir connectivity. Panel_15192 Panel_15192 4:05 PM 4:25 PM

This study describes the clinoforms and turbidite-system architecture of the southernmost Neuquen Basin margin. Excellent Jurassic clinoforms and turbidite-system architectures of the Los Molles Formation, Neuquen Basin expose continuous shelf to slope to basin-floor deposits for kilometers, with visible 2-300 meters high basin-margin clinoforms. Use of a high resolution digital elevation model (DEM) and satellite images, ground photo-panels and sedimentary measured sections allow the deposits to be correlated over 20 x 20 km, along depositional dip and strike. At the shelf edge the deposits have meter-thick structureless or cross-stratified sandstone to conglomerate beds, with abundant silicified wood that incise 30 m in places into the underlying muddy slope deposits. Slope deposits are dominated by thin laminated or structreless mud with thin (cm) sandstone beds. Isolated, up to5-10 m thick and tens to hundred meters wide, erosionally based sandstone and conglomerates with abundant mud clasts are interpreted as slope channels encased in mudstones. Toward the base of the slope, turbidite channels have a higher width-to-depth ratio, and they become laterally more extended (hundreds of meters). The basin floor deposits are interpreted as basin-floor turbidite channels and lobes based on their low relief (rarely erosional at the base) and lateral continuity for kilometers. These deposits are dominated by structureless and normally graded sandstone beds which are dm to m thick. Mapping of the individual 10-15 m basin-floor lobes shows the changes in facies from proximal to distal from dominantly structureless amalgamated and non-amalgamated sandstone beds to dominantly normal graded and laminated sandstone beds. Bed thickness increases from about 15 cm on average to 30 cm and then decreases again to 15 cm from proximal to distal. Grain size shows a more complex pattern but in general increases and then decreases form proximal to distal. On the basin floor there are also thick beds (up to 3-4 m) of pebble-conglomerate debris flow and mud flow deposits, that are more common in the older deposits (below the turbidite lobes) but also present within the lobe units. Lower to Middle Jurassic Los Molles Formation has been previously interpreted as syn-rift to post rift deposits. The architecture of the Neuqen Basin margin shows trends which are generally valid in many basins with a wide range of grain size and similar tectonic setting. This study describes the clinoforms and turbidite-system architecture of the southernmost Neuquen Basin margin. Excellent Jurassic clinoforms and turbidite-system architectures of the Los Molles Formation, Neuquen Basin expose continuous shelf to slope to basin-floor deposits for kilometers, with visible 2-300 meters high basin-margin clinoforms. Use of a high resolution digital elevation model (DEM) and satellite images, ground photo-panels and sedimentary measured sections allow the deposits to be correlated over 20 x 20 km, along depositional dip and strike. At the shelf edge the deposits have meter-thick structureless or cross-stratified sandstone to conglomerate beds, with abundant silicified wood that incise 30 m in places into the underlying muddy slope deposits. Slope deposits are dominated by thin laminated or structreless mud with thin (cm) sandstone beds. Isolated, up to5-10 m thick and tens to hundred meters wide, erosionally based sandstone and conglomerates with abundant mud clasts are interpreted as slope channels encased in mudstones. Toward the base of the slope, turbidite channels have a higher width-to-depth ratio, and they become laterally more extended (hundreds of meters). The basin floor deposits are interpreted as basin-floor turbidite channels and lobes based on their low relief (rarely erosional at the base) and lateral continuity for kilometers. These deposits are dominated by structureless and normally graded sandstone beds which are dm to m thick. Mapping of the individual 10-15 m basin-floor lobes shows the changes in facies from proximal to distal from dominantly structureless amalgamated and non-amalgamated sandstone beds to dominantly normal graded and laminated sandstone beds. Bed thickness increases from about 15 cm on average to 30 cm and then decreases again to 15 cm from proximal to distal. Grain size shows a more complex pattern but in general increases and then decreases form proximal to distal. On the basin floor there are also thick beds (up to 3-4 m) of pebble-conglomerate debris flow and mud flow deposits, that are more common in the older deposits (below the turbidite lobes) but also present within the lobe units. Lower to Middle Jurassic Los Molles Formation has been previously interpreted as syn-rift to post rift deposits. The architecture of the Neuqen Basin margin shows trends which are generally valid in many basins with a wide range of grain size and similar tectonic setting. Panel_15187 Panel_15187 4:25 PM 4:45 PM

Sediments deposited on slopes have been shown to deform in a dominantly down-slope direction driven by the force of gravity after deposition and burial. Multidirectional gravitational spreading and contemporaneous deformation can occur over a broad range of timescales and depths from shallow-subsurface intrastratal faulting and folding to complete remobilization of material at the seafloor. Submarine slope deformation and failure has important implications for various aspects of petroleum exploration and development including: 1) evaluating potential hazards for seafloor infrastructure, 2) reservoir characterization and prediction in slope strata, and 3) interpretation of discontinuous or chaotic seismic facies associated with slope deformation. While instances of intrastratal slope deformation (e.g. creep or slip) have been documented at the microscopic and seismic scales there is a paucity of examples at the scale of centimeters to 10’s of meters (reservoir scales). We present an outcrop example of syndepositional to synburial intrastratal slope deformation controlled by the distribution of turbidite deposits. Deep-marine slope deposits of the Cretaceous Tres Pasos Formation in the Magallanes Basin are exceptionally well exposed along a 3.5 km transect of the Rio Zamora at Cerro Mirador in southern Chile. Facies include: 1) thick-bedded sandstone facies (TSF; 25-200 cm beds), 2) thinly interbedded sandstone and mudstone facies (SMF; 5-30 cm beds), and 3) mudstone-prone facies (MPF; 1-10 cm beds). Facies transition significantly at the meter scale both laterally and vertically due to relative position within a composite succession of compensationally stacked, low aspect ratio sandstone-dominated bodies. Localized zones of cm- to m-scale faulting and subsidiary rotation and folding of discrete beds are bracketed by undeformed intervals that are present dominantly in SMF facies. Fault and fracture planes are parallel to downslope paleoflow orientation. The resulting interpretation is downslope creep deformation with localized slip planes (décollements) in fine-grained interbeds of MPF. The distribution of SMF and/or MPF is interpreted to be a key control on the locations of slip and associated deformation. These results highlight important dynamics and feedbacks in slope environments between depositional architecture, intrastratal deformation, and seafloor topography. Sediments deposited on slopes have been shown to deform in a dominantly down-slope direction driven by the force of gravity after deposition and burial. Multidirectional gravitational spreading and contemporaneous deformation can occur over a broad range of timescales and depths from shallow-subsurface intrastratal faulting and folding to complete remobilization of material at the seafloor. Submarine slope deformation and failure has important implications for various aspects of petroleum exploration and development including: 1) evaluating potential hazards for seafloor infrastructure, 2) reservoir characterization and prediction in slope strata, and 3) interpretation of discontinuous or chaotic seismic facies associated with slope deformation. While instances of intrastratal slope deformation (e.g. creep or slip) have been documented at the microscopic and seismic scales there is a paucity of examples at the scale of centimeters to 10’s of meters (reservoir scales). We present an outcrop example of syndepositional to synburial intrastratal slope deformation controlled by the distribution of turbidite deposits. Deep-marine slope deposits of the Cretaceous Tres Pasos Formation in the Magallanes Basin are exceptionally well exposed along a 3.5 km transect of the Rio Zamora at Cerro Mirador in southern Chile. Facies include: 1) thick-bedded sandstone facies (TSF; 25-200 cm beds), 2) thinly interbedded sandstone and mudstone facies (SMF; 5-30 cm beds), and 3) mudstone-prone facies (MPF; 1-10 cm beds). Facies transition significantly at the meter scale both laterally and vertically due to relative position within a composite succession of compensationally stacked, low aspect ratio sandstone-dominated bodies. Localized zones of cm- to m-scale faulting and subsidiary rotation and folding of discrete beds are bracketed by undeformed intervals that are present dominantly in SMF facies. Fault and fracture planes are parallel to downslope paleoflow orientation. The resulting interpretation is downslope creep deformation with localized slip planes (décollements) in fine-grained interbeds of MPF. The distribution of SMF and/or MPF is interpreted to be a key control on the locations of slip and associated deformation. These results highlight important dynamics and feedbacks in slope environments between depositional architecture, intrastratal deformation, and seafloor topography. Panel_15195 Panel_15195 4:45 PM 5:05 PM

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Coal companies have been mining thick coal beds in the Great Divide Basin over the past 120 years. This large synclinal feature has shallow, mineable coal near Point of Rocks on the west side and on the east side near Rawlins. Over 8.9 million short tons of coal were mined in Sweetwater County, WY in 2013, nearly half of that by underground methods. The mines supply fuel to the local Bridger Power Plant. At a modest one (1) percent growth rate per year for the next 100 years, over 1.53 billion short tons of coal could be mined from the Fort Union, Lance, and Almond formations in this area. The axis is north-south in the southern part of the basin, and trends N60W in the northwest part of the basin. It is one of two eastern sub-basins of the Greater Green River Basin in Wyoming. It is geologically distinct from the Washakie Basin to the south by the Wamsutter arch in the subsurface. The deepest part of the basin lies along the steep eastern flank of the Rawlins uplift, but the depocenter for latest Cretaceous and Paleocene strata lie in the northern part of the basin just south of the Wind River Mountains. Across the Great Divide Basin the Fort Union Formation thickens and increases in organic-rich bedding. The lower unit contains thick coals of mineable thickness near Point of Rocks, WY, on the east side of the Rock Springs Uplift. This coal-bearing interval thins out 10 miles south of the Black Butte Coal Mine. Paleocene Fort Union Formation strata at T25N R95W reach a maximum thickness of 4,720 ft. Net coal is usually less than 50 ft. The deepest Fort Union coals in T23N R94W are 6,605 ft, near the basin depo-center. The thinnest Fort Union Formation at 1,480 ft thick occurs near Wamsutter Field at T20S R93W. These syn-depositional alluvial continental sediments were deposited from nearby tectonic uplifts during Laramide time that formed the original Green River Basin. Only the lower part of the formation is organic rich containing subbituminous coal. WSGS coal geologists have correlated over 50 individual Fort Union coal beds from 1,992 petroleum wells and 3,562 coal exploration wells across the basin. These coals were mapped in the subsurface and correlated to known surface exposures. Shallow coal less than 3,500 ft was mapped for mining purposes, and coal calculations were determined in terms of thickness and depth. Significant minable coal resources were determined down dip from the active Bridger and Black Butte coal mines in Sweetwater County. Coal companies have been mining thick coal beds in the Great Divide Basin over the past 120 years. This large synclinal feature has shallow, mineable coal near Point of Rocks on the west side and on the east side near Rawlins. Over 8.9 million short tons of coal were mined in Sweetwater County, WY in 2013, nearly half of that by underground methods. The mines supply fuel to the local Bridger Power Plant. At a modest one (1) percent growth rate per year for the next 100 years, over 1.53 billion short tons of coal could be mined from the Fort Union, Lance, and Almond formations in this area. The axis is north-south in the southern part of the basin, and trends N60W in the northwest part of the basin. It is one of two eastern sub-basins of the Greater Green River Basin in Wyoming. It is geologically distinct from the Washakie Basin to the south by the Wamsutter arch in the subsurface. The deepest part of the basin lies along the steep eastern flank of the Rawlins uplift, but the depocenter for latest Cretaceous and Paleocene strata lie in the northern part of the basin just south of the Wind River Mountains. Across the Great Divide Basin the Fort Union Formation thickens and increases in organic-rich bedding. The lower unit contains thick coals of mineable thickness near Point of Rocks, WY, on the east side of the Rock Springs Uplift. This coal-bearing interval thins out 10 miles south of the Black Butte Coal Mine. Paleocene Fort Union Formation strata at T25N R95W reach a maximum thickness of 4,720 ft. Net coal is usually less than 50 ft. The deepest Fort Union coals in T23N R94W are 6,605 ft, near the basin depo-center. The thinnest Fort Union Formation at 1,480 ft thick occurs near Wamsutter Field at T20S R93W. These syn-depositional alluvial continental sediments were deposited from nearby tectonic uplifts during Laramide time that formed the original Green River Basin. Only the lower part of the formation is organic rich containing subbituminous coal. WSGS coal geologists have correlated over 50 individual Fort Union coal beds from 1,992 petroleum wells and 3,562 coal exploration wells across the basin. These coals were mapped in the subsurface and correlated to known surface exposures. Shallow coal less than 3,500 ft was mapped for mining purposes, and coal calculations were determined in terms of thickness and depth. Significant minable coal resources were determined down dip from the active Bridger and Black Butte coal mines in Sweetwater County. Panel_15643 Panel_15643 1:20 PM 1:40 PM

The cause of significant gas saturation in Pennsylvanian age coals and carbonaceous shale of the Cherokee Group, Cherokee and Forest City basins has been generally not well understood. Some coals are gas productive whereas others within the same strata are not. The Cherokee and Forest City basins are shallow intracratonic depressions that are sub-basins of the Pennsylvanian age Western Interior Basin. The coals in both basins were partially or completely subject to thermal maturation caused by migration of low temperature hydrothermal fluids expelled from the Anadarko, Ardmore and Arkoma basins in Oklahoma to the south that migrated north through the Cherokee and Forest City basins in late Carboniferous times. These fluids thermally altered the carbonaceous shale and coals within select areas of both basins causing significant gas generation. In both basins select seams are more highly gas saturated due to higher sulfur content in productive versus non-productive coals. The Riverton, Rowe, Weir-Pittsburg and Mulky coals and the Excello shale are gas productive in the Cherokee Basin. Only the Riverton coals in the Forest City Basin are productive. The area of primary production from unconventional reservoirs in the Cherokee Basin is also situated over the Silurian-Devonian age Chautauqua Arch. The coal bed methane production in the Forest City Basin is related to a localized intrusion(s) in the Leavenworth and Jefferson county area. Identifying the relationship between sedimentary thins, structural elements, timing of fluid migration, migration paths and sulfur contents of unconventional reservoirs provide an exploration model that can be useful in identifying potentially coal bed methane productive areas. The cause of significant gas saturation in Pennsylvanian age coals and carbonaceous shale of the Cherokee Group, Cherokee and Forest City basins has been generally not well understood. Some coals are gas productive whereas others within the same strata are not. The Cherokee and Forest City basins are shallow intracratonic depressions that are sub-basins of the Pennsylvanian age Western Interior Basin. The coals in both basins were partially or completely subject to thermal maturation caused by migration of low temperature hydrothermal fluids expelled from the Anadarko, Ardmore and Arkoma basins in Oklahoma to the south that migrated north through the Cherokee and Forest City basins in late Carboniferous times. These fluids thermally altered the carbonaceous shale and coals within select areas of both basins causing significant gas generation. In both basins select seams are more highly gas saturated due to higher sulfur content in productive versus non-productive coals. The Riverton, Rowe, Weir-Pittsburg and Mulky coals and the Excello shale are gas productive in the Cherokee Basin. Only the Riverton coals in the Forest City Basin are productive. The area of primary production from unconventional reservoirs in the Cherokee Basin is also situated over the Silurian-Devonian age Chautauqua Arch. The coal bed methane production in the Forest City Basin is related to a localized intrusion(s) in the Leavenworth and Jefferson county area. Identifying the relationship between sedimentary thins, structural elements, timing of fluid migration, migration paths and sulfur contents of unconventional reservoirs provide an exploration model that can be useful in identifying potentially coal bed methane productive areas. Panel_15644 Panel_15644 1:40 PM 2:00 PM

Up to now no exploitation breakthrough of coalbed methane (CBM) from low-rank coal in China has been achieved yet. However, a large number of low-rank coals have been continuously found in the formation of Jurassic middle-lower series, southern Junggar basin, China. How about coalbed methane in this area? This paper is to answer this question by means of researching low-rank coalbed methane (LRCBM) enrichment characteristics, establishing LRCBM accumulation model, and accomplishing LRCBM resource evaluation. Firstly, based on the analyses of the coal measure strata sedimentary sequence, sedimentary environment and its evolutionary process, the LRCBM enrichment characteristics of Jurassic middle-lower series southern Junggar basin is illustrated. Then, relying on a large number of data from laboratory tests and field tests, comprehensive analyses have been carried out, presenting the basic geological characteristics of this area, such as the coal seam distribution, petrology, reservoir property, coal rock thermal evolution, coal rock quality of 6 sections, as well as the CBM generating and bearing characteristics, the sealing properties of the CBM reservoir’s top and bottom rocks, the hydrogeological characteristics preserved by the CBM reservoir; Combining with the tectonic burial history, geothermal history, hydrocarbon evolution and CBM gas saturation changes, the LRCBM accumulation model of this area has been established. Finally, the LRCBM resources calculation and comprehensive evaluation of the 6 sections divided in this area points out the relatively favorable sections for further exploration in this area. The results show that the LRCBM resources of this area above 2000m amount to 3054.7×108m3, with the resource abundance between (0.42-11.65)×108m3/km2, and the resource abundance of Section 4 and Section 5 of this area is even higher than that of the CBM fields in the middle and east China, demonstrating very favorable exploitation prospect. Up to now no exploitation breakthrough of coalbed methane (CBM) from low-rank coal in China has been achieved yet. However, a large number of low-rank coals have been continuously found in the formation of Jurassic middle-lower series, southern Junggar basin, China. How about coalbed methane in this area? This paper is to answer this question by means of researching low-rank coalbed methane (LRCBM) enrichment characteristics, establishing LRCBM accumulation model, and accomplishing LRCBM resource evaluation. Firstly, based on the analyses of the coal measure strata sedimentary sequence, sedimentary environment and its evolutionary process, the LRCBM enrichment characteristics of Jurassic middle-lower series southern Junggar basin is illustrated. Then, relying on a large number of data from laboratory tests and field tests, comprehensive analyses have been carried out, presenting the basic geological characteristics of this area, such as the coal seam distribution, petrology, reservoir property, coal rock thermal evolution, coal rock quality of 6 sections, as well as the CBM generating and bearing characteristics, the sealing properties of the CBM reservoir’s top and bottom rocks, the hydrogeological characteristics preserved by the CBM reservoir; Combining with the tectonic burial history, geothermal history, hydrocarbon evolution and CBM gas saturation changes, the LRCBM accumulation model of this area has been established. Finally, the LRCBM resources calculation and comprehensive evaluation of the 6 sections divided in this area points out the relatively favorable sections for further exploration in this area. The results show that the LRCBM resources of this area above 2000m amount to 3054.7×108m3, with the resource abundance between (0.42-11.65)×108m3/km², and the resource abundance of Section 4 and Section 5 of this area is even higher than that of the CBM fields in the middle and east China, demonstrating very favorable exploitation prospect. Panel_15640 Panel_15640 2:00 PM 2:20 PM

Starting in 1994 a ground water, surface water and gas seepage monitoring network was set up in response to observed gas seepage near the subcrop of a producing Coal Bed Methane (CBM) formation and the Pine River in the San Juan Basin, southwestern Colorado. The null hypothesis was that CBM production was releasing gas at the subcrop due to downbasin CBM water pumping. The null hypothesis was tested using down hole video, packer testing, reservoir/seepage production analysis, temperature tracing, cation water quality, water age and potentiometric head trends. Based on the 20 years of data and analysis the CBM null hypothesis was rejected. Since there was no hydraulic connection between the subcrop and CBM production, there was no depletion from the Pine River. A new null hypothesis that gas seepage was due to long term precipitation trends was formulated in 2000 by the author. It continues to be accepted 13 years later. Starting in 1994 a ground water, surface water and gas seepage monitoring network was set up in response to observed gas seepage near the subcrop of a producing Coal Bed Methane (CBM) formation and the Pine River in the San Juan Basin, southwestern Colorado. The null hypothesis was that CBM production was releasing gas at the subcrop due to downbasin CBM water pumping. The null hypothesis was tested using down hole video, packer testing, reservoir/seepage production analysis, temperature tracing, cation water quality, water age and potentiometric head trends. Based on the 20 years of data and analysis the CBM null hypothesis was rejected. Since there was no hydraulic connection between the subcrop and CBM production, there was no depletion from the Pine River. A new null hypothesis that gas seepage was due to long term precipitation trends was formulated in 2000 by the author. It continues to be accepted 13 years later. Panel_15645 Panel_15645 2:20 PM 2:40 PM

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Integrated static and dynamic uncertainty workflows are a powerful tool for quantifying subsurface risks and guiding decisions during field development planning. A multi-disciplinary workflow that incorporates geophysical, geological and production uncertainties has been developed for the Jackdaw discovery, a High Pressure, High Temperature, gas-condensate field in the central North Sea. As a result of high well costs and the challenges of operating in extreme sub-surface conditions at depths approaching 19000 ft (5800 m), the exploration and appraisal programme, conducted between 2005 and 2012, was recognised as being unable to resolve various key uncertainties. In order to progress the development through the decision chain and provide key stakeholders with a robust, reasoned and accurate resource range, a key element in evaluating overall value, the sub-surface team developed innovative approaches to dealing with and quantifying the key uncertainties. This workflow draws on a geological model built with PETREL with uncertainty parameters defined within MEPO. In addition to modification of geological and petrophysical parameters, each realisation runs additional nested workflows. The first of these nested workflows modify the structure of the grid to account for gross rock volume and seismic interpretation uncertainty. The second workflow automatically calibrates the generated static model to the available drill stem test data. Each model realisation is simulated with ECLIPSE, with results sent back to MEPO for statistical analysis and the generation of probability distribution curves for both GIIP and reserves. Sensitivity analysis reveals the key uncertainty on in place volumes in both the appraised and un-appraised fault blocks are the gas-water contacts. However recovery from the reservoir is largely controlled by abandonment pressure and permeability. The reservoir comprises a bimodal permeability system that is primarily controlled by depositional facies. High permeability turbidite or gravity flow deposits are found within a background of low permeability, bioturbated shelfal sand. The shelf sand facies has core measured permeabilities of 0.005-1 mD (air permeability). As a result of this low permeability, uncertainty around the Klinkenberg correction factor and vertical permeability can significantly impact recovery. Integrated static and dynamic uncertainty workflows are a powerful tool for quantifying subsurface risks and guiding decisions during field development planning. A multi-disciplinary workflow that incorporates geophysical, geological and production uncertainties has been developed for the Jackdaw discovery, a High Pressure, High Temperature, gas-condensate field in the central North Sea. As a result of high well costs and the challenges of operating in extreme sub-surface conditions at depths approaching 19000 ft (5800 m), the exploration and appraisal programme, conducted between 2005 and 2012, was recognised as being unable to resolve various key uncertainties. In order to progress the development through the decision chain and provide key stakeholders with a robust, reasoned and accurate resource range, a key element in evaluating overall value, the sub-surface team developed innovative approaches to dealing with and quantifying the key uncertainties. This workflow draws on a geological model built with PETREL with uncertainty parameters defined within MEPO. In addition to modification of geological and petrophysical parameters, each realisation runs additional nested workflows. The first of these nested workflows modify the structure of the grid to account for gross rock volume and seismic interpretation uncertainty. The second workflow automatically calibrates the generated static model to the available drill stem test data. Each model realisation is simulated with ECLIPSE, with results sent back to MEPO for statistical analysis and the generation of probability distribution curves for both GIIP and reserves. Sensitivity analysis reveals the key uncertainty on in place volumes in both the appraised and un-appraised fault blocks are the gas-water contacts. However recovery from the reservoir is largely controlled by abandonment pressure and permeability. The reservoir comprises a bimodal permeability system that is primarily controlled by depositional facies. High permeability turbidite or gravity flow deposits are found within a background of low permeability, bioturbated shelfal sand. The shelf sand facies has core measured permeabilities of 0.005-1 mD (air permeability). As a result of this low permeability, uncertainty around the Klinkenberg correction factor and vertical permeability can significantly impact recovery. Panel_15012 Panel_15012 3:25 PM 3:45 PM

Most hydrocarbon producing basins of the world are dominated by vertical hydrocarbon migration. This vertical hydrocarbon migration is often directly detected in the seismic record as zones of vertically chaotic, low energy data, or “gas chimneys”. Geophysicists have noted that successful oil and gas wells are frequently less well imaged than wells over barren structures. Chimneys have often been observed in relationship to producing fields. However, this relationship has not been systematically documented, thus the need for a comprehensive atlas of these features. Chimneys can provide evidence of vertical hydrocarbon charge into a reservoir. Chimneys can also provide indications of the vertical seal integrity of the reservoir. The position of gas chimneys in relationship to the trap can also provide clues to the most likely fluid contacts. In mixed phase petroleum systems the morphology of chimneys can provide a clue to hydrocarbon phase. The diffuse nature of chimneys makes them difficult to map with 3D or 2D seismic data. Thus a method was developed to highlight and visualize these gas chimneys in normally processed seismic data. Gas chimneys are detected using a supervised neural network trained on reliable examples of gas chimneys. The resultant chimneys are validated based on a set of criteria. By detecting and mapping these chimneys, we can determine their origin (in a known or suspected source rock interval), their morphology, and how they are linked to known or suspected reservoirs. Using this chimney detection methodology, an atlas of chimney occurrences over known oil and gas fields (or discoveries) and dry holes in 3D seismic data is being compiled. Dry holes or sub-economic discoveries are chosen over valid anticlinal structures with effective reservoir (failure due to charge or seal). This atlas includes key interpreted and uninterpreted seismic lines through the wells to show the seismic character of identified chimneys. It also includes horizon slices, both above and below the reservoir intervals, to demonstrate charge and seal morphology. 3D images showing the relationship of chimney and reservoir geo-bodies are also displayed. Highlights of this atlas will be shown with examples from the Gulf of Mexico, North Sea, West Africa, Oriente Basin of Ecuador, Neuquén Basin of Argentina, and Gippsland Basin of Australia. The atlas is intended to provide useful analogs for hydrocarbon charge and seal assessment in various geologic settings. Most hydrocarbon producing basins of the world are dominated by vertical hydrocarbon migration. This vertical hydrocarbon migration is often directly detected in the seismic record as zones of vertically chaotic, low energy data, or “gas chimneys”. Geophysicists have noted that successful oil and gas wells are frequently less well imaged than wells over barren structures. Chimneys have often been observed in relationship to producing fields. However, this relationship has not been systematically documented, thus the need for a comprehensive atlas of these features. Chimneys can provide evidence of vertical hydrocarbon charge into a reservoir. Chimneys can also provide indications of the vertical seal integrity of the reservoir. The position of gas chimneys in relationship to the trap can also provide clues to the most likely fluid contacts. In mixed phase petroleum systems the morphology of chimneys can provide a clue to hydrocarbon phase. The diffuse nature of chimneys makes them difficult to map with 3D or 2D seismic data. Thus a method was developed to highlight and visualize these gas chimneys in normally processed seismic data. Gas chimneys are detected using a supervised neural network trained on reliable examples of gas chimneys. The resultant chimneys are validated based on a set of criteria. By detecting and mapping these chimneys, we can determine their origin (in a known or suspected source rock interval), their morphology, and how they are linked to known or suspected reservoirs. Using this chimney detection methodology, an atlas of chimney occurrences over known oil and gas fields (or discoveries) and dry holes in 3D seismic data is being compiled. Dry holes or sub-economic discoveries are chosen over valid anticlinal structures with effective reservoir (failure due to charge or seal). This atlas includes key interpreted and uninterpreted seismic lines through the wells to show the seismic character of identified chimneys. It also includes horizon slices, both above and below the reservoir intervals, to demonstrate charge and seal morphology. 3D images showing the relationship of chimney and reservoir geo-bodies are also displayed. Highlights of this atlas will be shown with examples from the Gulf of Mexico, North Sea, West Africa, Oriente Basin of Ecuador, Neuquén Basin of Argentina, and Gippsland Basin of Australia. The atlas is intended to provide useful analogs for hydrocarbon charge and seal assessment in various geologic settings. Panel_15009 Panel_15009 3:45 PM 4:05 PM

In Argentina, a number of fields have declined significantly while applying historical development strategies. These fields typically have a long production history and a large number of wells, often with incomplete and inconsistent data sets. Redevelopment strategies based on integrated models are needed to extract remaining oil, overcoming contradictory electric log signatures, old lithostratigraphic correlation and poor understanding of dynamic behavior. The fault-bounded Barrancas anticline is one of the aforementioned fields, with more than 400 wells and over 60 years of oil production history. Early water-flood showed an excellent response in the field; yet production has strongly declined and significant oil remains in the subsurface (RF 26%). The primary objective of this study was to quantify remaining opportunities and obtain an optimized development plan, justifying further investment in this old field. Facies associations coming from core and outcrop analyses interpreted the Barrancas Formation as a North-South prograding alluvial-ephemeral system. Changes between progradational and retrogradational periods were used as chronostratigraphic correlation surfaces. Areal trends in reservoir quality, resulting from this stratigraphic model, were clearly reflected in uneven production distribution across the field, but were not as clearly shown in the outdated and contradictory electric logs responses. Log data was in fact found to be inconsistent, due to low resolution Spontaneous Potential profiles and volcanic-affected Gamma Ray logs. Since production history was the most consistent reservoir response, it was decided to use dynamic data upfront, as the main constrain for reservoir characterization and modelling. By doing so, different geological scenarios were tested and compared, letting dynamic data guide the appropriate hierarchy, porosity and connectivity of reservoir bodies. To aid integration and guarantee consistency between static and dynamic models, the geological model was deliberately built at a scale that could be simulated. Dynamic models built this way managed to overturn existing preconceptions about the field (reservoir quality distribution, distinct OWCs, aquifer impact) and to successfully predict the existence of unexploited flank oil and unswept central zones. Even when the field was supposed to be mature, the study proved existence of enough opportunities to support additional investments. In Argentina, a number of fields have declined significantly while applying historical development strategies. These fields typically have a long production history and a large number of wells, often with incomplete and inconsistent data sets. Redevelopment strategies based on integrated models are needed to extract remaining oil, overcoming contradictory electric log signatures, old lithostratigraphic correlation and poor understanding of dynamic behavior. The fault-bounded Barrancas anticline is one of the aforementioned fields, with more than 400 wells and over 60 years of oil production history. Early water-flood showed an excellent response in the field; yet production has strongly declined and significant oil remains in the subsurface (RF 26%). The primary objective of this study was to quantify remaining opportunities and obtain an optimized development plan, justifying further investment in this old field. Facies associations coming from core and outcrop analyses interpreted the Barrancas Formation as a North-South prograding alluvial-ephemeral system. Changes between progradational and retrogradational periods were used as chronostratigraphic correlation surfaces. Areal trends in reservoir quality, resulting from this stratigraphic model, were clearly reflected in uneven production distribution across the field, but were not as clearly shown in the outdated and contradictory electric logs responses. Log data was in fact found to be inconsistent, due to low resolution Spontaneous Potential profiles and volcanic-affected Gamma Ray logs. Since production history was the most consistent reservoir response, it was decided to use dynamic data upfront, as the main constrain for reservoir characterization and modelling. By doing so, different geological scenarios were tested and compared, letting dynamic data guide the appropriate hierarchy, porosity and connectivity of reservoir bodies. To aid integration and guarantee consistency between static and dynamic models, the geological model was deliberately built at a scale that could be simulated. Dynamic models built this way managed to overturn existing preconceptions about the field (reservoir quality distribution, distinct OWCs, aquifer impact) and to successfully predict the existence of unexploited flank oil and unswept central zones. Even when the field was supposed to be mature, the study proved existence of enough opportunities to support additional investments. Panel_15008 Panel_15008 4:05 PM 4:25 PM

A new geophysical exploration tool sourced by billions of naturally occurring electrical discharges from cloud to earth has been developed. Analysis of sixteen years of recorded North American lightning data have revealed non-random patterns of lightning strikes. When these data are cleaned, lightning strike density and newly-defined lightning attribute maps show interesting correlations to surface and subsurface geology. To date, applications of this new and naturally sourced electromagnetic (NSEM) analysis technique include the exploration for groundwater, minerals and hydrocarbons, the identification of geohazards, as well as the optimal location of pipe and power lines and where additional insulation and grounding are required. Although lightning is a worldwide phenomenon guided by meteorological conditions, the precise location of strikes and their individual attributes are guided by shallow earth or terralevis electromagnetic currents. These currents are in turn highly influenced by lateral geological inhomogeneity caused by faults, fractures, mineralization, pore-fluids, and salinity variations. Lightning strikes and their attributes cluster around geologic features. Since surface and subsurface geology is a function of geologic time, geology is constant relative to the short time spans associated with lightning databases. This enables lightning data to be stacked similar to the way multi-fold seismic data is stacked and processed. When processed in this manner, lightning strike density and attribute maps show clusters and lineations which appear to correlate to fresh water, some surface projections of faults, near surface fluvial depositional patterns, and possibly to hydrocarbon seeps, salt domes, hydrocarbons, and mineralization. A case study from the Texas Gulf Coast shows a “Rise Time” lightning attribute map that identified twenty-eight anomalies, each correlating back to a Tertiary aged oil or gas field. Ongoing research utilizing patent pending algorithms show the electrical information contained in the lightning databases enables the calculation of resistivity and permittivity volumes. From these volumes, slices and cross-sections can be displayed, analyzed, and interpreted similar to the way 3D seismic data are evaluated. These volumes can be calculated and displayed at the same bin spacing as any available 3D data volume where the right lightning databases are available, thus allowing the data to be easily integrated with available seismic and subsurface data. Although NSEM is a derivative of potential field data having lower frequency and resolution, it has tremendous value for building regional geological frameworks. It can help identify trapping faults in the search for hydrocarbons, prospective mineral acreage, and hydrocarbon migration pathways. NSEM is a useful new reconnaissance mapping tool that can be used to determine where to acquire geophysical or geochemical data for detailed follow-up evaluations. In addition, NSEM has potential to assist in a wide range of non-exploration applications such as the identification of subsurface contaminant plumes, the placement of power lines and pipelines, the identification of surface and subsurface geohazards, and the mitigation of risk associated with lightning strikes. A disaster investigation report is referenced to illustrate how an awareness of lightning strike density could have helped avoid a deadly coal bed methane explosion. NSEM is a new geophysical data type with wide application to society. This data is significantly less expensive to acquire, process, and interpret than most, if not all, geophysical techniques on the market today. Its cost is about 1/100th of what it would cost to acquire typical 3-D seismic data and an entire project can be completed within two months. Three-dimensional resistivity and permittivity data can be viewed in cross-section and as horizontal slices. It can also be scaled to the same display parameters as any 2-D or 3-D geophysical data, which facilitates its calibration to other geophysical and geological data. A new geophysical exploration tool sourced by billions of naturally occurring electrical discharges from cloud to earth has been developed. Analysis of sixteen years of recorded North American lightning data have revealed non-random patterns of lightning strikes. When these data are cleaned, lightning strike density and newly-defined lightning attribute maps show interesting correlations to surface and subsurface geology. To date, applications of this new and naturally sourced electromagnetic (NSEM) analysis technique include the exploration for groundwater, minerals and hydrocarbons, the identification of geohazards, as well as the optimal location of pipe and power lines and where additional insulation and grounding are required. Although lightning is a worldwide phenomenon guided by meteorological conditions, the precise location of strikes and their individual attributes are guided by shallow earth or terralevis electromagnetic currents. These currents are in turn highly influenced by lateral geological inhomogeneity caused by faults, fractures, mineralization, pore-fluids, and salinity variations. Lightning strikes and their attributes cluster around geologic features. Since surface and subsurface geology is a function of geologic time, geology is constant relative to the short time spans associated with lightning databases. This enables lightning data to be stacked similar to the way multi-fold seismic data is stacked and processed. When processed in this manner, lightning strike density and attribute maps show clusters and lineations which appear to correlate to fresh water, some surface projections of faults, near surface fluvial depositional patterns, and possibly to hydrocarbon seeps, salt domes, hydrocarbons, and mineralization. A case study from the Texas Gulf Coast shows a “Rise Time” lightning attribute map that identified twenty-eight anomalies, each correlating back to a Tertiary aged oil or gas field. Ongoing research utilizing patent pending algorithms show the electrical information contained in the lightning databases enables the calculation of resistivity and permittivity volumes. From these volumes, slices and cross-sections can be displayed, analyzed, and interpreted similar to the way 3D seismic data are evaluated. These volumes can be calculated and displayed at the same bin spacing as any available 3D data volume where the right lightning databases are available, thus allowing the data to be easily integrated with available seismic and subsurface data. Although NSEM is a derivative of potential field data having lower frequency and resolution, it has tremendous value for building regional geological frameworks. It can help identify trapping faults in the search for hydrocarbons, prospective mineral acreage, and hydrocarbon migration pathways. NSEM is a useful new reconnaissance mapping tool that can be used to determine where to acquire geophysical or geochemical data for detailed follow-up evaluations. In addition, NSEM has potential to assist in a wide range of non-exploration applications such as the identification of subsurface contaminant plumes, the placement of power lines and pipelines, the identification of surface and subsurface geohazards, and the mitigation of risk associated with lightning strikes. A disaster investigation report is referenced to illustrate how an awareness of lightning strike density could have helped avoid a deadly coal bed methane explosion. NSEM is a new geophysical data type with wide application to society. This data is significantly less expensive to acquire, process, and interpret than most, if not all, geophysical techniques on the market today. Its cost is about 1/100th of what it would cost to acquire typical 3-D seismic data and an entire project can be completed within two months. Three-dimensional resistivity and permittivity data can be viewed in cross-section and as horizontal slices. It can also be scaled to the same display parameters as any 2-D or 3-D geophysical data, which facilitates its calibration to other geophysical and geological data. Panel_15011 Panel_15011 4:25 PM 4:45 PM

Technological advances in both equipment and computer software have enabled the implementation of new approaches in generation of mineralogical datasets at petroleum wellsites. These datasets are currently utilized by hydraulic fracturing engineers to assist in designing optimized fracture stage intervals in horizontal wellbores, rather than using evenly spaced intervals between treatment stages. Mineralogical data is generated by downhole wireline logging tools, and on drill cuttings, conventional wholecores, and rotary sidewall coreplugs utilizing a variety of analytical instrumentation techniques. This paper documents a study undertaken to assess mineralogical datasets generated on comparable samples, focused on evaluating analytical limitations and variances, toward obtaining consistent mineralogical results. Instrumentation typically used to generate these datasets include x-ray diffraction (XRD), x-ray fluorescence (XRF), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), fourier transform infrared spectroscopy (FTIR), and inductively coupled plasma techniques (ICP mass spectroscopy or ICP optical emission spectroscopy). Variables introduced into the analysis in addition to the different analytical techniques include sample types and sizes, sampling methods, sample preparation, drilling mud contaminants, lithological heterogeneity, and depth correlations between cuttings, cores, and wireline measurements. Equipment destined for wellsite analysis was evaluated in a controlled laboratory environment using reference mineral standards and standard mixtures to understand testing limitations and refine mineral phase calculations. Mineral terminologies, classifications, compositions, and the resulting databases were reviewed for consistency. Multiple cuttings and core sample sets from conventional sandstones, carbonates, and current mudrock plays such as the Eagle Ford and Marcellus shales were sub-divided and analyzed to allow direct comparisons of generated datasets. This study yielded increased confidence in wellsite and laboratory analyses, including caveats where necessary, procedural guidelines for each analytical technique, and verification of deliverables appropriate to unconventional mudstone reservoirs. Example datasets, graphical comparisons, and report formats are included. The resultant wellsite datasets, in tandem with additional wellsite analytics, enhance confidence in optimized fracture stage interval decisions. Technological advances in both equipment and computer software have enabled the implementation of new approaches in generation of mineralogical datasets at petroleum wellsites. These datasets are currently utilized by hydraulic fracturing engineers to assist in designing optimized fracture stage intervals in horizontal wellbores, rather than using evenly spaced intervals between treatment stages. Mineralogical data is generated by downhole wireline logging tools, and on drill cuttings, conventional wholecores, and rotary sidewall coreplugs utilizing a variety of analytical instrumentation techniques. This paper documents a study undertaken to assess mineralogical datasets generated on comparable samples, focused on evaluating analytical limitations and variances, toward obtaining consistent mineralogical results. Instrumentation typically used to generate these datasets include x-ray diffraction (XRD), x-ray fluorescence (XRF), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), fourier transform infrared spectroscopy (FTIR), and inductively coupled plasma techniques (ICP mass spectroscopy or ICP optical emission spectroscopy). Variables introduced into the analysis in addition to the different analytical techniques include sample types and sizes, sampling methods, sample preparation, drilling mud contaminants, lithological heterogeneity, and depth correlations between cuttings, cores, and wireline measurements. Equipment destined for wellsite analysis was evaluated in a controlled laboratory environment using reference mineral standards and standard mixtures to understand testing limitations and refine mineral phase calculations. Mineral terminologies, classifications, compositions, and the resulting databases were reviewed for consistency. Multiple cuttings and core sample sets from conventional sandstones, carbonates, and current mudrock plays such as the Eagle Ford and Marcellus shales were sub-divided and analyzed to allow direct comparisons of generated datasets. This study yielded increased confidence in wellsite and laboratory analyses, including caveats where necessary, procedural guidelines for each analytical technique, and verification of deliverables appropriate to unconventional mudstone reservoirs. Example datasets, graphical comparisons, and report formats are included. The resultant wellsite datasets, in tandem with additional wellsite analytics, enhance confidence in optimized fracture stage interval decisions. Panel_15010 Panel_15010 4:45 PM 5:05 PM