James Keay - Academia.edu (original) (raw)

Papers by James Keay

Research paper thumbnail of Deepwater Santos Basin – Huge Undrilled Pre-Salt Potential

First HGS and EAGE Conference on Latin America, 2019

Research paper thumbnail of Seismic reservoir characterization of Bone Spring and Wolfcamp Formations in the Delaware Basin — A case study: Part 1

Interpretation, Nov 1, 2020

The Delaware and Midland Basins are multistacked plays with production being drawn from different... more The Delaware and Midland Basins are multistacked plays with production being drawn from different zones. Of the various prospective zones in the Delaware Basin, the Bone Spring and Wolfcamp Formations are the most productive and thus are the most drilled zones. To understand the reservoirs of interest and identify the hydrocarbon sweet spots, a 3D seismic inversion project was undertaken in the northern part of the Delaware Basin in 2018. We have examined the reservoir characterization exercise for this dataset in two parts. In addition to a brief description of the geology, we evaluate the challenges faced in performing seismic inversion for characterizing multistacked plays. The key elements that lend confidence in seismic inversion and the quantitative predictions made therefrom are well-to-seismic ties, proper data conditioning, robust initial models, and adequate parameterization of inversion analysis. We examine the limitations of a conventional approach associated with these individual steps and determine how to overcome them. Later work will first elaborate on the uncertainties associated with input parameters required for executing rock-physics analysis and then evaluate the proposed robust statistical approach for defining the different lithofacies.

Research paper thumbnail of Detection and Distribution of Thief Perm in the Late Albian Mauddud Formation, Sabiriyah and Raudhatain Fields, Kuwait: A Dual Porosity Dual Permeability Methodology for Model Implementation

Second Arabian Plate Geology Workshop 2010, 2010

Research paper thumbnail of Depositional Environment and Controls on Porosity Development and Distribution, in the Late Albian Mauddud Formation, Sabiriyah and Raudhatain Fields, Kuwait, as Input to a Geocellular Model

All Days, 2009

Detailed description of core (19,500 ft) from 57 wells in the Cretaceous (Late Albian) Mauddud Fo... more Detailed description of core (19,500 ft) from 57 wells in the Cretaceous (Late Albian) Mauddud Formation, Sabiriyah and Raudhatain Fields, Northern Kuwait, formed the basis for an updated depositional model. Numerous reservoir units occur within carbonate-dominated, mixed carbonate-clastic, and siliciclastic-dominated intervals. Core description and interpretation software (WellCAD/CoreCAD) was used to record observations and interpretations in digital format which was integrated into a master database for geocellular modeling, static, and dynamic reservoir modeling. The predictive depositional model demonstrates lithofacies distribution, primary depositional and secondary diagenetic controls on porosity occurrence, distribution of high permeability ‘thief zones common in both fields, and distribution of flow baffles and barriers within the vertical sequence. The Lower Mauddud comprises carbonate-dominated shallowing-upward cycles deposited in a carbonate ramp environment and locali...

Research paper thumbnail of Synergy between Industry Intelligence and Technological Innovation to Address Our Climate Goal

Research paper thumbnail of New Insights on the Alaskan Chukchi Sea

Research paper thumbnail of The Utica - Point Pleasant Shale

Research paper thumbnail of Depositional Environment and Controls on Porosity Development and Distribution, in the Late Albian Mauddud Formation, Sabiriyah and Raudhatain Fields, Kuwait, as Input to a Geocellular Model

Kuwait International Petroleum Conference and Exhibition, 2009

Detailed description of core (19,500 ft) from 57 wells in the Cretaceous (Late Albian) Mauddud Fo... more Detailed description of core (19,500 ft) from 57 wells in the Cretaceous (Late Albian) Mauddud Formation, Sabiriyah and Raudhatain Fields, Northern Kuwait, formed the basis for an updated depositional model. Numerous reservoir units occur within carbonate-dominated, mixed carbonate-clastic, and siliciclastic-dominated intervals. Core description and interpretation software (WellCAD/CoreCAD) was used to record observations and interpretations in digital format which was integrated into a master database for geocellular modeling, static, and dynamic reservoir modeling. The predictive depositional model demonstrates lithofacies distribution, primary depositional and secondary diagenetic controls on porosity occurrence, distribution of high permeability 'thief' zones common in both fields, and distribution of flow baffles and barriers within the vertical sequence. The Lower Mauddud comprises carbonate-dominated shallowing-upward cycles deposited in a carbonate ramp environment a...

Research paper thumbnail of Shale gas reservoir characterization workflows

Summary As shale gas resources have emerged as a viable energy source, their characterization has... more Summary As shale gas resources have emerged as a viable energy source, their characterization has gained significance. The organic content in these shales which are measured by their TOC ratings, influence the compressional and shear velocities as well as the density and anisotropy in these formations. Consequently, it should be possible to detect changes in TOC from the surface seismic response. Besides TOC, different shale formations have different properties in terms of maturation, gas-in-place, permeability, and brittleness. We discuss different workflows for characterizing shale formations that involve well log data as well as seismic data.

Research paper thumbnail of Powder River Basin Production Review from 2011 Through 2018: How Refinements in Completions and Operations Have Led to Increasing Production in the Upper Cretaceous Formations of Campbell and Converse Counties, Wyoming

Proceedings of the 7th Unconventional Resources Technology Conference, 2019

Research paper thumbnail of Seismic Reservoir Characterization of the Bone Spring and Wolfcamp Formations in the Delaware Basin with Efforts at Quantitative Interpretation—A Case Study

Proceedings of the 7th Unconventional Resources Technology Conference

Research paper thumbnail of Correlation of TOC CoreMeasurements to Wireline Logs across the Delaware Basin

Proceedings of the 7th Unconventional Resources Technology Conference, 2019

Research paper thumbnail of Extended Abstract: Structural Styles and Regional Play Types in the Mexican Offshore from New Seismic Data

Article based on an extended abstract published in the GCAGS Transactions (see footnote reference... more Article based on an extended abstract published in the GCAGS Transactions (see footnote reference below), which is available as part of the entire 2016 GCAGS Transactions volume via the GCAGS Bookstore at the Bureau of Economic Geology (www.beg.utexas.edu) or as an individual document via AAPG Datapages, Inc. (www.datapages.com), and delivered as an oral presentation at the 66th Annual GCAGS Convention and 63rd Annual GCSSEPM Meeting in Corpus Christi, Texas, September 18–20, 2016.

Research paper thumbnail of Two Inversion Case Studies from the SCOOP and STACK Area of Oklahoma

Proceedings of the 7th Unconventional Resources Technology Conference, 2019

We showcase here the seismic characterization of the Meramec and the Devonian Woodford in the SCO... more We showcase here the seismic characterization of the Meramec and the Devonian Woodford in the SCOOP/STACK trend in Oklahoma formations, using multicomponent seismic data in the STACK area and the conventional vertical component seismic data in the SCOOP area, using deterministic prestack impedance inversion. The objective is to demonstrate how the joint impedance inversion carried out over seismic data from the STACK area was used to derive rockphysics parameters (Young’s modulus and Poisson’s ratio), and how the derived sweet spots compared with those obtained with just the conventional seismic data. Finally, we compare the unsupervised machine learning (ML) facies classification results with those obtained from the impedance inversions mentioned above.

Research paper thumbnail of SDRs or presalt synrift graben? – Insight from an integrated case study of presalt reflectors in Campos Basin, offshore Brazil

Seaward-dipping reflectors (SDRs) represent flood basalts rapidly extruded during either rifting ... more Seaward-dipping reflectors (SDRs) represent flood basalts rapidly extruded during either rifting or initially subaerial sea-floor spreading (Jackson et al., 2000). Where highquality geophysical data is not available, SDRs can be easily confused with a half graben, when both have reflections dipping seaward and both are near to the Continent-Ocean Boundary (COB). Differentiating SDRs and a half graben would have a huge impact to hydrocarbon exploration – a half graben in a rift basin is one of the major exploration targets but SDRs usually indicate that there is no exploration potential. We investigate a highresolution 3D dataset in the Campos Basin, reprocess the dataset with gravity constraint and interpret a presalt graben system where previous workers interpret as SDRs.

Research paper thumbnail of Quantitative Interpretation Efforts in Seismic Reservoir Characterization of Utica-Point Pleasant Shale – A Case Study

Proceedings of the 6th Unconventional Resources Technology Conference

Utica shale is one of the major source rocks in Ohio and extends across much of eastern US. Its o... more Utica shale is one of the major source rocks in Ohio and extends across much of eastern US. Its organic richness, high content of calcite, and development of extensive organic porosity makes it a perfect unconventional play and has gained attention of oil and gas industry. The primary target zone in the Utica includes Utica, Point Pleasant, and Trenton intervals. In the present study, we attempt to identify the sweet-spots within the Point-Pleasant interval using 3D seismic data, available well data, and other relevant data. This has been done by way of organic richness and brittleness estimation in the rock intervals. The brittleness has been derived using rock-physics parameters such as Young's modulus and Poisson's ratio. Deterministic simultaneous inversion along with neural network approach have been followed in order to compute rock-physics parameters and density using seismic data. The consistency of sweet spots identified based on the seismic data with the available production data emphasize the integration of seismic data with all other relevant data. We find that the Point Pleasant formation does not seem to follow the commonly followed variation in terms of low Poisson's ratio and high Young's modulus for brittle pockets. Instead, by restricting the values of Poisson's ratio and examining the variation of Young's modulus, we were able to determine the brittleness behavior within the Point Pleasant interval. Combining the brittleness behavior with the organic richness determined through the density content, we were able to pick sweet spots in the Point Pleasant interval which matches the production data. Through this case study, we emphasize the integration of 3D surface seismic data with all other relevant data so as to accurately characterize the Point Pleasant formation.

Research paper thumbnail of New life for old wells – Repurposing oil and gas well data for geothermal prospecting

First International Meeting for Applied Geoscience & Energy Expanded Abstracts

With a well-organized production database, rich in detail, and high-resolution basin-wide tempera... more With a well-organized production database, rich in detail, and high-resolution basin-wide temperature models, we can make inferences to areas and zones where formation temperatures are favorable for geothermal applications. Constraining the data by favorable temperature and filtering on well production criteria enables rapid prospecting across large areas.

Research paper thumbnail of Efforts at effective seismic reservoir characterization of Bone Spring and Wolfcamp formations in the Delaware Basin: A case study

SEG Technical Program Expanded Abstracts 2019

The Delaware and Midland Basins are multistacked plays with production being drawn from different... more The Delaware and Midland Basins are multistacked plays with production being drawn from different zones. Of the various prospective zones in the Delaware Basin, the Bone Spring and Wolfcamp formations are the most productive and thus are the most-drilled zones. A 3D seismic survey was acquired in the northern part of Delaware Basin and after processing was picked up, to understand the reservoirs of interest and pick the sweet spots. We describe the whole reservoir characterization exercise that was carried out on this data in three different phases. We discuss phase 1 here, beginning with a brief description of the geology of the area and the stratigraphic column, and going on to the well ties for the different available wells over the 3D seismic survey, estimation of the shear curves where the measured shear curves were missing, the generation of an accurate low-frequency model for impedance inversion, preconditioning of the prestack seismic data, use of different lithotrends in inversion and finally the prestack simultaneous impedance inversion.

Research paper thumbnail of Challenges and uncertainty in the seismic reservoir characterization of Bone Spring and Wolfcamp formations in the Delaware Basin using rock physics

SEG Technical Program Expanded Abstracts 2019

Research paper thumbnail of SCOOP and STACK inversion case studies

SEG Technical Program Expanded Abstracts 2018

The Mississippian section, in particular the Meramec and the Devonian Woodford continue to be the... more The Mississippian section, in particular the Meramec and the Devonian Woodford continue to be the preferred investment targets in the SCOOP/STACK trend in Oklahoma We showcase here the seismic characterization of these formations using multicomponent seismic data in the STACK area and the conventional vertical component seismic data in the SCOOP area, using deterministic prestack impedance inversion. The joint impedance inversion carried out over seismic data from the STACK area was used to derive rockphysics parameters (Young's modulus and Poisson's ratio), which showed the sweet spots that are distinct spatially, rather than bleeding off at the edges. The added advantage of joint inversion was that the density attribute could also be derived therefrom, which was not possible for the data from the STACK area. In addition to density, the results from prestack joint impedance inversion have been found to be superior to the simultaneous inversion. The equivalent attributes (besides density) derived for the SCOOP area also show promise.

Research paper thumbnail of Deepwater Santos Basin – Huge Undrilled Pre-Salt Potential

First HGS and EAGE Conference on Latin America, 2019

Research paper thumbnail of Seismic reservoir characterization of Bone Spring and Wolfcamp Formations in the Delaware Basin — A case study: Part 1

Interpretation, Nov 1, 2020

The Delaware and Midland Basins are multistacked plays with production being drawn from different... more The Delaware and Midland Basins are multistacked plays with production being drawn from different zones. Of the various prospective zones in the Delaware Basin, the Bone Spring and Wolfcamp Formations are the most productive and thus are the most drilled zones. To understand the reservoirs of interest and identify the hydrocarbon sweet spots, a 3D seismic inversion project was undertaken in the northern part of the Delaware Basin in 2018. We have examined the reservoir characterization exercise for this dataset in two parts. In addition to a brief description of the geology, we evaluate the challenges faced in performing seismic inversion for characterizing multistacked plays. The key elements that lend confidence in seismic inversion and the quantitative predictions made therefrom are well-to-seismic ties, proper data conditioning, robust initial models, and adequate parameterization of inversion analysis. We examine the limitations of a conventional approach associated with these individual steps and determine how to overcome them. Later work will first elaborate on the uncertainties associated with input parameters required for executing rock-physics analysis and then evaluate the proposed robust statistical approach for defining the different lithofacies.

Research paper thumbnail of Detection and Distribution of Thief Perm in the Late Albian Mauddud Formation, Sabiriyah and Raudhatain Fields, Kuwait: A Dual Porosity Dual Permeability Methodology for Model Implementation

Second Arabian Plate Geology Workshop 2010, 2010

Research paper thumbnail of Depositional Environment and Controls on Porosity Development and Distribution, in the Late Albian Mauddud Formation, Sabiriyah and Raudhatain Fields, Kuwait, as Input to a Geocellular Model

All Days, 2009

Detailed description of core (19,500 ft) from 57 wells in the Cretaceous (Late Albian) Mauddud Fo... more Detailed description of core (19,500 ft) from 57 wells in the Cretaceous (Late Albian) Mauddud Formation, Sabiriyah and Raudhatain Fields, Northern Kuwait, formed the basis for an updated depositional model. Numerous reservoir units occur within carbonate-dominated, mixed carbonate-clastic, and siliciclastic-dominated intervals. Core description and interpretation software (WellCAD/CoreCAD) was used to record observations and interpretations in digital format which was integrated into a master database for geocellular modeling, static, and dynamic reservoir modeling. The predictive depositional model demonstrates lithofacies distribution, primary depositional and secondary diagenetic controls on porosity occurrence, distribution of high permeability ‘thief zones common in both fields, and distribution of flow baffles and barriers within the vertical sequence. The Lower Mauddud comprises carbonate-dominated shallowing-upward cycles deposited in a carbonate ramp environment and locali...

Research paper thumbnail of Synergy between Industry Intelligence and Technological Innovation to Address Our Climate Goal

Research paper thumbnail of New Insights on the Alaskan Chukchi Sea

Research paper thumbnail of The Utica - Point Pleasant Shale

Research paper thumbnail of Depositional Environment and Controls on Porosity Development and Distribution, in the Late Albian Mauddud Formation, Sabiriyah and Raudhatain Fields, Kuwait, as Input to a Geocellular Model

Kuwait International Petroleum Conference and Exhibition, 2009

Detailed description of core (19,500 ft) from 57 wells in the Cretaceous (Late Albian) Mauddud Fo... more Detailed description of core (19,500 ft) from 57 wells in the Cretaceous (Late Albian) Mauddud Formation, Sabiriyah and Raudhatain Fields, Northern Kuwait, formed the basis for an updated depositional model. Numerous reservoir units occur within carbonate-dominated, mixed carbonate-clastic, and siliciclastic-dominated intervals. Core description and interpretation software (WellCAD/CoreCAD) was used to record observations and interpretations in digital format which was integrated into a master database for geocellular modeling, static, and dynamic reservoir modeling. The predictive depositional model demonstrates lithofacies distribution, primary depositional and secondary diagenetic controls on porosity occurrence, distribution of high permeability 'thief' zones common in both fields, and distribution of flow baffles and barriers within the vertical sequence. The Lower Mauddud comprises carbonate-dominated shallowing-upward cycles deposited in a carbonate ramp environment a...

Research paper thumbnail of Shale gas reservoir characterization workflows

Summary As shale gas resources have emerged as a viable energy source, their characterization has... more Summary As shale gas resources have emerged as a viable energy source, their characterization has gained significance. The organic content in these shales which are measured by their TOC ratings, influence the compressional and shear velocities as well as the density and anisotropy in these formations. Consequently, it should be possible to detect changes in TOC from the surface seismic response. Besides TOC, different shale formations have different properties in terms of maturation, gas-in-place, permeability, and brittleness. We discuss different workflows for characterizing shale formations that involve well log data as well as seismic data.

Research paper thumbnail of Powder River Basin Production Review from 2011 Through 2018: How Refinements in Completions and Operations Have Led to Increasing Production in the Upper Cretaceous Formations of Campbell and Converse Counties, Wyoming

Proceedings of the 7th Unconventional Resources Technology Conference, 2019

Research paper thumbnail of Seismic Reservoir Characterization of the Bone Spring and Wolfcamp Formations in the Delaware Basin with Efforts at Quantitative Interpretation—A Case Study

Proceedings of the 7th Unconventional Resources Technology Conference

Research paper thumbnail of Correlation of TOC CoreMeasurements to Wireline Logs across the Delaware Basin

Proceedings of the 7th Unconventional Resources Technology Conference, 2019

Research paper thumbnail of Extended Abstract: Structural Styles and Regional Play Types in the Mexican Offshore from New Seismic Data

Article based on an extended abstract published in the GCAGS Transactions (see footnote reference... more Article based on an extended abstract published in the GCAGS Transactions (see footnote reference below), which is available as part of the entire 2016 GCAGS Transactions volume via the GCAGS Bookstore at the Bureau of Economic Geology (www.beg.utexas.edu) or as an individual document via AAPG Datapages, Inc. (www.datapages.com), and delivered as an oral presentation at the 66th Annual GCAGS Convention and 63rd Annual GCSSEPM Meeting in Corpus Christi, Texas, September 18–20, 2016.

Research paper thumbnail of Two Inversion Case Studies from the SCOOP and STACK Area of Oklahoma

Proceedings of the 7th Unconventional Resources Technology Conference, 2019

We showcase here the seismic characterization of the Meramec and the Devonian Woodford in the SCO... more We showcase here the seismic characterization of the Meramec and the Devonian Woodford in the SCOOP/STACK trend in Oklahoma formations, using multicomponent seismic data in the STACK area and the conventional vertical component seismic data in the SCOOP area, using deterministic prestack impedance inversion. The objective is to demonstrate how the joint impedance inversion carried out over seismic data from the STACK area was used to derive rockphysics parameters (Young’s modulus and Poisson’s ratio), and how the derived sweet spots compared with those obtained with just the conventional seismic data. Finally, we compare the unsupervised machine learning (ML) facies classification results with those obtained from the impedance inversions mentioned above.

Research paper thumbnail of SDRs or presalt synrift graben? – Insight from an integrated case study of presalt reflectors in Campos Basin, offshore Brazil

Seaward-dipping reflectors (SDRs) represent flood basalts rapidly extruded during either rifting ... more Seaward-dipping reflectors (SDRs) represent flood basalts rapidly extruded during either rifting or initially subaerial sea-floor spreading (Jackson et al., 2000). Where highquality geophysical data is not available, SDRs can be easily confused with a half graben, when both have reflections dipping seaward and both are near to the Continent-Ocean Boundary (COB). Differentiating SDRs and a half graben would have a huge impact to hydrocarbon exploration – a half graben in a rift basin is one of the major exploration targets but SDRs usually indicate that there is no exploration potential. We investigate a highresolution 3D dataset in the Campos Basin, reprocess the dataset with gravity constraint and interpret a presalt graben system where previous workers interpret as SDRs.

Research paper thumbnail of Quantitative Interpretation Efforts in Seismic Reservoir Characterization of Utica-Point Pleasant Shale – A Case Study

Proceedings of the 6th Unconventional Resources Technology Conference

Utica shale is one of the major source rocks in Ohio and extends across much of eastern US. Its o... more Utica shale is one of the major source rocks in Ohio and extends across much of eastern US. Its organic richness, high content of calcite, and development of extensive organic porosity makes it a perfect unconventional play and has gained attention of oil and gas industry. The primary target zone in the Utica includes Utica, Point Pleasant, and Trenton intervals. In the present study, we attempt to identify the sweet-spots within the Point-Pleasant interval using 3D seismic data, available well data, and other relevant data. This has been done by way of organic richness and brittleness estimation in the rock intervals. The brittleness has been derived using rock-physics parameters such as Young's modulus and Poisson's ratio. Deterministic simultaneous inversion along with neural network approach have been followed in order to compute rock-physics parameters and density using seismic data. The consistency of sweet spots identified based on the seismic data with the available production data emphasize the integration of seismic data with all other relevant data. We find that the Point Pleasant formation does not seem to follow the commonly followed variation in terms of low Poisson's ratio and high Young's modulus for brittle pockets. Instead, by restricting the values of Poisson's ratio and examining the variation of Young's modulus, we were able to determine the brittleness behavior within the Point Pleasant interval. Combining the brittleness behavior with the organic richness determined through the density content, we were able to pick sweet spots in the Point Pleasant interval which matches the production data. Through this case study, we emphasize the integration of 3D surface seismic data with all other relevant data so as to accurately characterize the Point Pleasant formation.

Research paper thumbnail of New life for old wells – Repurposing oil and gas well data for geothermal prospecting

First International Meeting for Applied Geoscience & Energy Expanded Abstracts

With a well-organized production database, rich in detail, and high-resolution basin-wide tempera... more With a well-organized production database, rich in detail, and high-resolution basin-wide temperature models, we can make inferences to areas and zones where formation temperatures are favorable for geothermal applications. Constraining the data by favorable temperature and filtering on well production criteria enables rapid prospecting across large areas.

Research paper thumbnail of Efforts at effective seismic reservoir characterization of Bone Spring and Wolfcamp formations in the Delaware Basin: A case study

SEG Technical Program Expanded Abstracts 2019

The Delaware and Midland Basins are multistacked plays with production being drawn from different... more The Delaware and Midland Basins are multistacked plays with production being drawn from different zones. Of the various prospective zones in the Delaware Basin, the Bone Spring and Wolfcamp formations are the most productive and thus are the most-drilled zones. A 3D seismic survey was acquired in the northern part of Delaware Basin and after processing was picked up, to understand the reservoirs of interest and pick the sweet spots. We describe the whole reservoir characterization exercise that was carried out on this data in three different phases. We discuss phase 1 here, beginning with a brief description of the geology of the area and the stratigraphic column, and going on to the well ties for the different available wells over the 3D seismic survey, estimation of the shear curves where the measured shear curves were missing, the generation of an accurate low-frequency model for impedance inversion, preconditioning of the prestack seismic data, use of different lithotrends in inversion and finally the prestack simultaneous impedance inversion.

Research paper thumbnail of Challenges and uncertainty in the seismic reservoir characterization of Bone Spring and Wolfcamp formations in the Delaware Basin using rock physics

SEG Technical Program Expanded Abstracts 2019

Research paper thumbnail of SCOOP and STACK inversion case studies

SEG Technical Program Expanded Abstracts 2018

The Mississippian section, in particular the Meramec and the Devonian Woodford continue to be the... more The Mississippian section, in particular the Meramec and the Devonian Woodford continue to be the preferred investment targets in the SCOOP/STACK trend in Oklahoma We showcase here the seismic characterization of these formations using multicomponent seismic data in the STACK area and the conventional vertical component seismic data in the SCOOP area, using deterministic prestack impedance inversion. The joint impedance inversion carried out over seismic data from the STACK area was used to derive rockphysics parameters (Young's modulus and Poisson's ratio), which showed the sweet spots that are distinct spatially, rather than bleeding off at the edges. The added advantage of joint inversion was that the density attribute could also be derived therefrom, which was not possible for the data from the STACK area. In addition to density, the results from prestack joint impedance inversion have been found to be superior to the simultaneous inversion. The equivalent attributes (besides density) derived for the SCOOP area also show promise.