Advancements in Geochemistry and Geomicrobiology of Energy Resources (AGGER)
Active
By Geology, Energy & Minerals Science Center
May 23, 2022
The AGGER project’s purpose is to advance the understanding of geologic energy sources, generation, composition, movement, and production potential, including resource recovery from energy wastes.
This purpose manifests in three broad objectives:
- Assessing subsurface microorganisms in order to stimulate or retard biogenic gas production;
- Linking macroscale geologic energy phenomena (e.g., petroleum recoverability or carbon sequestration) to nanoscale parameters (e.g., pore accessibility); and
- Developing standardized approaches to evaluate both the resource potential and environmental risks of energy related wastes.
Achieving these objectives relates to the DOI Strategic Objective 3.2 Current Energy Needs Are Met Through Balanced Resource Use, and informs Congress, State and Federal agencies, private organizations, and the public on the U.S. energy endowment.
The AGGER project is currently divided into 7 research tasks, detailed below, and funds three research laboratories.
- Controls on microbial methanogenesis in shale deposits and strategies for enhancement - Task leads: Elliott Barnhart and Matthew Varonka
- Structure and composition of energy materials - Task lead: Aaron Jubb
- NORM products, byproducts and wastes from energy resource life cycles - Task lead: Bonnie McDevitt
- Spectroscopic investigations of energy materials - Task lead: Aaron Jubb
- Remote sensing techniques to quantify energy resources in wastes at abandoned mines - Task lead: Bernard Hubbard
- Scoping innovative approaches in advanced field measurements and data analysis - Task lead: Elisha ‘Eli’ Moore
- Assessing critical minerals and contaminants in coal mine drainage - Task lead: Bonnie McDevitt
The following 3 laboratories are associated with the AGGER project:
- Eastern Energy and Environmental Laboratory (EEEL)
- Raman Spectroscopy Laboratory (RSL)
- Naturally Occurring Radioactive Material Laboratory (NORM)
The data releases listed below are associated with the AGGER project.
Filter Total Items: 17
Coal mine drainage effluents and associated solids major, trace, rare earth element and radium concentrations collected from Pennsylvania, USA
Discharges from abandoned coal mines and associated mine wastes represent historic and persistent sources of pollution in the Appalachian Basin, United States. In this study, we conducted the first-ever survey of radium (Ra) in coal mine drainage (CMD) water and solid samples in the United States. Samples were collected from 4 untreated coal mine discharges and 9 treated coal mine discharges (i.e.
Total neutron scattering of methane in Niobrara Formation samples at the wet-gas maturity level
Petroleum within unconventional source-rock reservoirs is hosted in organic matter and mineral pore space as well as in voids and microfractures. Recent work has shown that for source-rock reservoirs in the dry gas window, significant portions of methane (CH4), the main component of petroleum at elevated maturities, can be stored within fine organic matter porosity. However, within reservoirs at l
Evidence for strain induced graphitization across a ductile fault zone
A suite of slate samples collected along a 2 km transect crossing the Lishan Fault in central Taiwan were evaluated to assess the role of ductile strain energy in natural graphitization at greenschist facies metamorphic conditions. Scanning electron microscope (SEM) imaging documents phyllosilicate and quartz replacement textures consistent cleavage development via dissolution-precipitation proces
Carbon and Nitrogen in Sediments from Hg-Contaminated Streams and Lakes in Texas, Virginia, and Tennessee
Sediment samples were collected from mercury-contaminated streams and lakes in Texas, Virginia, and Tennessee and were analyzed for total carbon (TC) and total nitrogen (TN). A portion of the sample was combusted at 550 degrees C for 2 hours prior to analysis to remove the organic carbon and nitrogen, thus giving total inorganic carbon (TIC) and total inorganic nitrogen (TIN). Total organic carbon
Strain induced molecular heterogeneity in ancient sedimentary organic matter mapped at nanoscales using optical photothermal infrared spectroscopy
Here we report ultra-high resolution infrared mapping of organic matter functional group distribution in Tasmanites (algal microfossils) from the Upper Devonian Ohio Shale using optical photothermal infrared spectroscopy (O-PTIR). O-PTIR is capable of rapidly measuring the vibrational response of samples in situ with ~500-nm spatial resolution, well below the infrared diffraction limit. Our result
Textural occurrence and organic porosity of solid bitumen in shales
This study presents Raman spectroscopic data paired with scanning electron microscopy (SEM) to assess solid bitumen composition and porosity development as a function of solid bitumen texture and association with minerals. A series of hydrous pyrolysis experiments (1-103 days, 300-370°C) using a low maturity (0.25% solid bitumen reflectance, BRo), high total organic carbon [(TOC), 14.0 wt. %] New
Absorbance and Fluorescence Excitation-Emission Matrix Data for Produced Waters from Oil and Gas Producing Basins in the United States
Waters co-produced during petroleum extraction are normally considered wastes but are also possible resources, especially in water-stressed regions. Produced waters can be chemically complex. High salinity, naturally occurring radioactive materials, and organic substances derived from the producing formation can complicate treatment processes. Rapid screening methods to characterize produced water
TOC, Reflectance and Raman Data from Eocene Green River Mahogany Zone
Geological models for petroleum generation suggest thermal conversion of oil-prone sedimentary organic matter in the presence of water promotes increased liquid saturate yield, whereas absence of water causes formation of an aromatic, cross-linked solid bitumen residue. To test the influence of exchangeable hydrogen from water, organic-rich (22 wt. percent total organic carbon, TOC) mudrock sample
Data Compiled on historical water use, spatial land disturbance, aquifer disturbance and uranium produced by In Situ Recovery of Uranium from Sandstone Hosted Uranium Deposits in the South Texas Coastal Plain, USA
This data release contains data on historical water use, spatial land disturbance, and spatial aquifer disturbances related to in situ recovery (ISR) uranium extraction per unit of uranium produced. These data were compiled from published and publicly available references including journal articles, government reports, industry reports and company reporting documents for regulatory compliance and
Chemistry Data from the Birney Test Site, Montana, 2018-2020
Data were collected to monitor geochemistry before and after an injection designed to stimulate microbial methanogenesis in the shallow Flowers-Goodale coal bed, near Birney in southeastern Montana. Waters from wells completed in the Flowers-Goodale, Nance, Knobloch, and Terret coalbeds at the Birney Test Site were sampled. Geochemical characterization of the water included non-purgeable dissolved
Microbiology of the Utica Shale
In order to determine the innate microbial community of shale gas reservoirs and how they are impacted by hydraulic fracturing, this study analyzed biomass collected from produced water and rock from hydraulically fractured wells in the Utica Shale. The samples include rock chips from a drill core from one Utica well, produced water from that same Utica well, and produced water from 12 different U
Atomic Force Microscopy-based Infrared Spectroscopy Data within Immature Eagle Ford Shale at the Nanometer-scale
The nanoscale molecular composition of kerogen is a challenging parameter to characterize given the chemical and structural complexity exhibited by this important biopolymer. However, kerogen composition will strongly impact its reactivity and so is a critical parameter to understand petroleum generation processes during kerogen catagenesis. The recent advent of tip-enhanced analytical methods, su
The publications listed below are associated with the AGGER project.
Filter Total Items: 44
Deformation-induced graphitization and muscovite recrystallization in a ductile fault zone
A suite of slate samples collected along a 2 km transect crossing the Lishan fault in central Taiwan were evaluated to assess the role of ductile deformation in natural graphitization at lower greenschist facies metamorphic conditions. The process of natural aromatization, or graphitization, of an organic precursor is well established as a thermally driven process; however, experimental studies ha
Authors
Martha (Rebecca) Stokes, Aaron M. Jubb, Ryan J. McAleer, David Bish, Robert Wintsch
Krumholzibacteriota and Deltaproteobacteria contain rare genetic potential to liberate carbon from monoaromatic compounds in subsurface coal seams
Biogenic methane in subsurface coal seam environments is produced by diverse consortia of microbes. Although this methane is useful for global energy security, it remains unclear which microbes can liberate carbon from the coal. Most of this carbon is relatively resistant to biodegradation, as it is contained within aromatic rings. Thus, to explore for coal-degrading taxa in the subsurface, this s
Authors
Bronwyn C. Campbell, Paul Greenfield, Elliott Barnhart, Se Gong, David J. Midgley, Ian T. Paulsen, Simon C. George
Uranium redox and deposition transitions embedded in deep-time geochemical models and mineral chemistry networks
Uranium (U) is an important global energy resource and a redox sensitive trace element that reflects changing environmental conditions and geochemical cycling. The redox evolution of U mineral chemistry can be interrogated to understand the formation and distribution of U deposits and the redox processes involved in U geochemistry throughout Earth history. In this study, geochemical modeling using
Authors
Elisha Kelly Moore, J. Li, Ao Zhang, Jihua Hao, Shaunna M. Morrison, Daniel Hummer, Nathan Yee
Exploring the uncertainty of machine learning models and geostatistical mapping of rare earth element potential in Indiana coals, USA
Rare earth elements and yttrium (REEs) have a wide range of applications in high- and low-carbon technologies. The strategic significance of REEs has grown due to their expanding applications in manufacturing industries and the constrained availability of these essential resources. This research explores the applicability of machine learning models and their uncertainty for assessing the REE poten
Authors
Snehamoy Chatterjee, C. Özgen Karacan, Maria Mastalerz
Hyperspectral (VNIR-SWIR) analysis of roll front uranium host rocks and industrial minerals from Karnes and Live Oak Counties, Texas Coastal Plain
VNIR-SWIR (400–2500 nm) reflectance measurements were made on the surfaces of various cores, cuttings and sample splits of sedimentary rocks from the Tertiary Jackson Group, and Catahoula, Oakville and Goliad Formations. These rocks vary in composition and texture from mudstone and claystone to sandstone and are known host rocks for roll front uranium occurrences in Karnes and Live Oak Counties, T
Authors
Bernard E. Hubbard, Tanya J. Gallegos, Victoria G. Stengel, Todd M. Hoefen, Raymond F. Kokaly, Brent Elliott
Insights into glendonite formation from the upper Oligocene Sagavanirktok Formation, North Slope, Alaska
The type locality for the upper Oligocene Nuwok Member of the Sagavanirktok Formation (Carter Creek, North Slope, Alaska, USA) contains abundant occurrence of glendonite, a pseudomorph after the calcium carbonate mineral ikaite, which typically forms in the shallow subsurface of cold marine sediments. The region during the time of Nuwok Member deposition was located at a high latitude, similar to
Authors
John W. Counts, Madeleine Vickers, Martha (Rebecca) Stokes, Whittney Spivey, Kristina Frank Gardner, Jean Self-Trail, Jared T. Gooley, Ryan J. McAleer, Aaron M. Jubb, David W. Houseknecht, Richard O. Lease, Neil Patrick Griffis, Martin S. Vickers, Kasia Śliwińska, Hannah Gail Dooley Tompkins, Adam M. Hudson
Evaluation of portable Raman spectroscopic analysis for source-rock thermal maturity assessments on bulk crushed rock
This study presents a simplified method and empirical relationships for determining organic matter thermal maturity using a portable Raman system equipped with a 785 nm laser, for analysis of crushed, whole-rock samples. Suites of rocks represented by shale and coal samples with various mineralogical composition, thermal maturity, and total organic carbon (TOC) were used to test the method and bui
Authors
Martha (Rebecca) Stokes, Aaron M. Jubb, Paul C. Hackley, Justin E. Birdwell, Elliott Barnhart, Clint Scott, Jenna L. Shelton, Margaret M. Sanders, Javin J. Hatcherian
Methane pore accessibility, densification, and accommodation by organic matter in the Niobrara Formation at wet-gas thermal maturity conditions
Petroleum within unconventional source-rock reservoirs is hosted in organic matter and mineral pore space as well as in voids and microfractures. Recent work has shown that for source-rock reservoirs in the dry gas window, significant portions of methane (CH4), the main component of petroleum at elevated maturities, can be stored within fine (<5 nm) organic matter porosity. However, within reservo
Authors
Aaron M. Jubb, Leslie F. Ruppert, Tristan G. A. Youngs, Tom Headen, Justin E. Birdwell, Michael Cheshire, Martha (Rebecca) Stokes
Mapping abandoned uranium mine features using Worldview-3 imagery in portions of Karnes, Atascosa and Live Oak Counties, Texas
Worldview-3 (WV3) 16-band multispectral data were used to map exposed bedrock and mine waste piles associated with legacy open-pit mining of sandstone-hosted roll-front uranium deposits along the South Texas Coastal Plain. We used the “spectral hourglass” approach to extract spectral endmembers representative of these features from the image. This approach first requires calibrating the imagery to
Authors
Bernard E. Hubbard, Tanya J. Gallegos, Victoria G. Stengel
Broadening the perspectives of sedimentary organic matter analysis to understand Earth system response to change
This paper broadens the description of sedimentary organic matter from the conventional use of coal petrography to include palynological and geochemical sedimentary organic matter. Palynological sedimentary organic matter includes all chemically resistant organic microfossils, such as pollen and spores, dinocysts, microforaminifera (chitinoid-like linings of foraminifera), microscopic algae, charc
Authors
Debra A. Willard, Leslie F. Ruppert
Thermal evolution of graptolite and solid bitumen properties at high maturity under natural and artificial conditions
To refine the use of graptolite and solid bitumen as thermal proxies at overmature conditions, we evaluated their evolution via Raman and infrared (IR) spectroscopies, reflectance, and geochemical screening using high-temperature pyrolysis experiments in comparison to naturally matured samples. Naturally matured samples included marine shales from the overmature Upper Ordovician Wufeng-Lower Silur
Authors
Jianyang Song, Paul C. Hackley, Margaret M. Sanders, Aaron M. Jubb, Qingyong Luo
Algal amendment enhances biogenic methane production from coals of different thermal maturity
The addition of small amounts of algal biomass to stimulate methane production in coal seams is a promising low carbon renewable coalbed methane enhancement technique. However, little is known about how the addition of algal biomass amendment affects methane production from coals of different thermal maturity. Here, we show that biogenic methane can be produced from five coals ranging in rank from
Authors
George A. Platt, Katherine J. Davis, Hannah D. Schweitzer, Heidi J. Smith, Matthew W. Fields, Elliott Barnhart, Robin Gerlach
The AGGER project’s purpose is to advance the understanding of geologic energy sources, generation, composition, movement, and production potential, including resource recovery from energy wastes.
This purpose manifests in three broad objectives:
- Assessing subsurface microorganisms in order to stimulate or retard biogenic gas production;
- Linking macroscale geologic energy phenomena (e.g., petroleum recoverability or carbon sequestration) to nanoscale parameters (e.g., pore accessibility); and
- Developing standardized approaches to evaluate both the resource potential and environmental risks of energy related wastes.
Achieving these objectives relates to the DOI Strategic Objective 3.2 Current Energy Needs Are Met Through Balanced Resource Use, and informs Congress, State and Federal agencies, private organizations, and the public on the U.S. energy endowment.
The AGGER project is currently divided into 7 research tasks, detailed below, and funds three research laboratories.
- Controls on microbial methanogenesis in shale deposits and strategies for enhancement - Task leads: Elliott Barnhart and Matthew Varonka
- Structure and composition of energy materials - Task lead: Aaron Jubb
- NORM products, byproducts and wastes from energy resource life cycles - Task lead: Bonnie McDevitt
- Spectroscopic investigations of energy materials - Task lead: Aaron Jubb
- Remote sensing techniques to quantify energy resources in wastes at abandoned mines - Task lead: Bernard Hubbard
- Scoping innovative approaches in advanced field measurements and data analysis - Task lead: Elisha ‘Eli’ Moore
- Assessing critical minerals and contaminants in coal mine drainage - Task lead: Bonnie McDevitt
The following 3 laboratories are associated with the AGGER project:
- Eastern Energy and Environmental Laboratory (EEEL)
- Raman Spectroscopy Laboratory (RSL)
- Naturally Occurring Radioactive Material Laboratory (NORM)
The data releases listed below are associated with the AGGER project.
Filter Total Items: 17
Coal mine drainage effluents and associated solids major, trace, rare earth element and radium concentrations collected from Pennsylvania, USA
Discharges from abandoned coal mines and associated mine wastes represent historic and persistent sources of pollution in the Appalachian Basin, United States. In this study, we conducted the first-ever survey of radium (Ra) in coal mine drainage (CMD) water and solid samples in the United States. Samples were collected from 4 untreated coal mine discharges and 9 treated coal mine discharges (i.e.
Total neutron scattering of methane in Niobrara Formation samples at the wet-gas maturity level
Petroleum within unconventional source-rock reservoirs is hosted in organic matter and mineral pore space as well as in voids and microfractures. Recent work has shown that for source-rock reservoirs in the dry gas window, significant portions of methane (CH4), the main component of petroleum at elevated maturities, can be stored within fine organic matter porosity. However, within reservoirs at l
Evidence for strain induced graphitization across a ductile fault zone
A suite of slate samples collected along a 2 km transect crossing the Lishan Fault in central Taiwan were evaluated to assess the role of ductile strain energy in natural graphitization at greenschist facies metamorphic conditions. Scanning electron microscope (SEM) imaging documents phyllosilicate and quartz replacement textures consistent cleavage development via dissolution-precipitation proces
Carbon and Nitrogen in Sediments from Hg-Contaminated Streams and Lakes in Texas, Virginia, and Tennessee
Sediment samples were collected from mercury-contaminated streams and lakes in Texas, Virginia, and Tennessee and were analyzed for total carbon (TC) and total nitrogen (TN). A portion of the sample was combusted at 550 degrees C for 2 hours prior to analysis to remove the organic carbon and nitrogen, thus giving total inorganic carbon (TIC) and total inorganic nitrogen (TIN). Total organic carbon
Strain induced molecular heterogeneity in ancient sedimentary organic matter mapped at nanoscales using optical photothermal infrared spectroscopy
Here we report ultra-high resolution infrared mapping of organic matter functional group distribution in Tasmanites (algal microfossils) from the Upper Devonian Ohio Shale using optical photothermal infrared spectroscopy (O-PTIR). O-PTIR is capable of rapidly measuring the vibrational response of samples in situ with ~500-nm spatial resolution, well below the infrared diffraction limit. Our result
Textural occurrence and organic porosity of solid bitumen in shales
This study presents Raman spectroscopic data paired with scanning electron microscopy (SEM) to assess solid bitumen composition and porosity development as a function of solid bitumen texture and association with minerals. A series of hydrous pyrolysis experiments (1-103 days, 300-370°C) using a low maturity (0.25% solid bitumen reflectance, BRo), high total organic carbon [(TOC), 14.0 wt. %] New
Absorbance and Fluorescence Excitation-Emission Matrix Data for Produced Waters from Oil and Gas Producing Basins in the United States
Waters co-produced during petroleum extraction are normally considered wastes but are also possible resources, especially in water-stressed regions. Produced waters can be chemically complex. High salinity, naturally occurring radioactive materials, and organic substances derived from the producing formation can complicate treatment processes. Rapid screening methods to characterize produced water
TOC, Reflectance and Raman Data from Eocene Green River Mahogany Zone
Geological models for petroleum generation suggest thermal conversion of oil-prone sedimentary organic matter in the presence of water promotes increased liquid saturate yield, whereas absence of water causes formation of an aromatic, cross-linked solid bitumen residue. To test the influence of exchangeable hydrogen from water, organic-rich (22 wt. percent total organic carbon, TOC) mudrock sample
Data Compiled on historical water use, spatial land disturbance, aquifer disturbance and uranium produced by In Situ Recovery of Uranium from Sandstone Hosted Uranium Deposits in the South Texas Coastal Plain, USA
This data release contains data on historical water use, spatial land disturbance, and spatial aquifer disturbances related to in situ recovery (ISR) uranium extraction per unit of uranium produced. These data were compiled from published and publicly available references including journal articles, government reports, industry reports and company reporting documents for regulatory compliance and
Chemistry Data from the Birney Test Site, Montana, 2018-2020
Data were collected to monitor geochemistry before and after an injection designed to stimulate microbial methanogenesis in the shallow Flowers-Goodale coal bed, near Birney in southeastern Montana. Waters from wells completed in the Flowers-Goodale, Nance, Knobloch, and Terret coalbeds at the Birney Test Site were sampled. Geochemical characterization of the water included non-purgeable dissolved
Microbiology of the Utica Shale
In order to determine the innate microbial community of shale gas reservoirs and how they are impacted by hydraulic fracturing, this study analyzed biomass collected from produced water and rock from hydraulically fractured wells in the Utica Shale. The samples include rock chips from a drill core from one Utica well, produced water from that same Utica well, and produced water from 12 different U
Atomic Force Microscopy-based Infrared Spectroscopy Data within Immature Eagle Ford Shale at the Nanometer-scale
The nanoscale molecular composition of kerogen is a challenging parameter to characterize given the chemical and structural complexity exhibited by this important biopolymer. However, kerogen composition will strongly impact its reactivity and so is a critical parameter to understand petroleum generation processes during kerogen catagenesis. The recent advent of tip-enhanced analytical methods, su
The publications listed below are associated with the AGGER project.
Filter Total Items: 44
Deformation-induced graphitization and muscovite recrystallization in a ductile fault zone
A suite of slate samples collected along a 2 km transect crossing the Lishan fault in central Taiwan were evaluated to assess the role of ductile deformation in natural graphitization at lower greenschist facies metamorphic conditions. The process of natural aromatization, or graphitization, of an organic precursor is well established as a thermally driven process; however, experimental studies ha
Authors
Martha (Rebecca) Stokes, Aaron M. Jubb, Ryan J. McAleer, David Bish, Robert Wintsch
Krumholzibacteriota and Deltaproteobacteria contain rare genetic potential to liberate carbon from monoaromatic compounds in subsurface coal seams
Biogenic methane in subsurface coal seam environments is produced by diverse consortia of microbes. Although this methane is useful for global energy security, it remains unclear which microbes can liberate carbon from the coal. Most of this carbon is relatively resistant to biodegradation, as it is contained within aromatic rings. Thus, to explore for coal-degrading taxa in the subsurface, this s
Authors
Bronwyn C. Campbell, Paul Greenfield, Elliott Barnhart, Se Gong, David J. Midgley, Ian T. Paulsen, Simon C. George
Uranium redox and deposition transitions embedded in deep-time geochemical models and mineral chemistry networks
Uranium (U) is an important global energy resource and a redox sensitive trace element that reflects changing environmental conditions and geochemical cycling. The redox evolution of U mineral chemistry can be interrogated to understand the formation and distribution of U deposits and the redox processes involved in U geochemistry throughout Earth history. In this study, geochemical modeling using
Authors
Elisha Kelly Moore, J. Li, Ao Zhang, Jihua Hao, Shaunna M. Morrison, Daniel Hummer, Nathan Yee
Exploring the uncertainty of machine learning models and geostatistical mapping of rare earth element potential in Indiana coals, USA
Rare earth elements and yttrium (REEs) have a wide range of applications in high- and low-carbon technologies. The strategic significance of REEs has grown due to their expanding applications in manufacturing industries and the constrained availability of these essential resources. This research explores the applicability of machine learning models and their uncertainty for assessing the REE poten
Authors
Snehamoy Chatterjee, C. Özgen Karacan, Maria Mastalerz
Hyperspectral (VNIR-SWIR) analysis of roll front uranium host rocks and industrial minerals from Karnes and Live Oak Counties, Texas Coastal Plain
VNIR-SWIR (400–2500 nm) reflectance measurements were made on the surfaces of various cores, cuttings and sample splits of sedimentary rocks from the Tertiary Jackson Group, and Catahoula, Oakville and Goliad Formations. These rocks vary in composition and texture from mudstone and claystone to sandstone and are known host rocks for roll front uranium occurrences in Karnes and Live Oak Counties, T
Authors
Bernard E. Hubbard, Tanya J. Gallegos, Victoria G. Stengel, Todd M. Hoefen, Raymond F. Kokaly, Brent Elliott
Insights into glendonite formation from the upper Oligocene Sagavanirktok Formation, North Slope, Alaska
The type locality for the upper Oligocene Nuwok Member of the Sagavanirktok Formation (Carter Creek, North Slope, Alaska, USA) contains abundant occurrence of glendonite, a pseudomorph after the calcium carbonate mineral ikaite, which typically forms in the shallow subsurface of cold marine sediments. The region during the time of Nuwok Member deposition was located at a high latitude, similar to
Authors
John W. Counts, Madeleine Vickers, Martha (Rebecca) Stokes, Whittney Spivey, Kristina Frank Gardner, Jean Self-Trail, Jared T. Gooley, Ryan J. McAleer, Aaron M. Jubb, David W. Houseknecht, Richard O. Lease, Neil Patrick Griffis, Martin S. Vickers, Kasia Śliwińska, Hannah Gail Dooley Tompkins, Adam M. Hudson
Evaluation of portable Raman spectroscopic analysis for source-rock thermal maturity assessments on bulk crushed rock
This study presents a simplified method and empirical relationships for determining organic matter thermal maturity using a portable Raman system equipped with a 785 nm laser, for analysis of crushed, whole-rock samples. Suites of rocks represented by shale and coal samples with various mineralogical composition, thermal maturity, and total organic carbon (TOC) were used to test the method and bui
Authors
Martha (Rebecca) Stokes, Aaron M. Jubb, Paul C. Hackley, Justin E. Birdwell, Elliott Barnhart, Clint Scott, Jenna L. Shelton, Margaret M. Sanders, Javin J. Hatcherian
Methane pore accessibility, densification, and accommodation by organic matter in the Niobrara Formation at wet-gas thermal maturity conditions
Petroleum within unconventional source-rock reservoirs is hosted in organic matter and mineral pore space as well as in voids and microfractures. Recent work has shown that for source-rock reservoirs in the dry gas window, significant portions of methane (CH4), the main component of petroleum at elevated maturities, can be stored within fine (<5 nm) organic matter porosity. However, within reservo
Authors
Aaron M. Jubb, Leslie F. Ruppert, Tristan G. A. Youngs, Tom Headen, Justin E. Birdwell, Michael Cheshire, Martha (Rebecca) Stokes
Mapping abandoned uranium mine features using Worldview-3 imagery in portions of Karnes, Atascosa and Live Oak Counties, Texas
Worldview-3 (WV3) 16-band multispectral data were used to map exposed bedrock and mine waste piles associated with legacy open-pit mining of sandstone-hosted roll-front uranium deposits along the South Texas Coastal Plain. We used the “spectral hourglass” approach to extract spectral endmembers representative of these features from the image. This approach first requires calibrating the imagery to
Authors
Bernard E. Hubbard, Tanya J. Gallegos, Victoria G. Stengel
Broadening the perspectives of sedimentary organic matter analysis to understand Earth system response to change
This paper broadens the description of sedimentary organic matter from the conventional use of coal petrography to include palynological and geochemical sedimentary organic matter. Palynological sedimentary organic matter includes all chemically resistant organic microfossils, such as pollen and spores, dinocysts, microforaminifera (chitinoid-like linings of foraminifera), microscopic algae, charc
Authors
Debra A. Willard, Leslie F. Ruppert
Thermal evolution of graptolite and solid bitumen properties at high maturity under natural and artificial conditions
To refine the use of graptolite and solid bitumen as thermal proxies at overmature conditions, we evaluated their evolution via Raman and infrared (IR) spectroscopies, reflectance, and geochemical screening using high-temperature pyrolysis experiments in comparison to naturally matured samples. Naturally matured samples included marine shales from the overmature Upper Ordovician Wufeng-Lower Silur
Authors
Jianyang Song, Paul C. Hackley, Margaret M. Sanders, Aaron M. Jubb, Qingyong Luo
Algal amendment enhances biogenic methane production from coals of different thermal maturity
The addition of small amounts of algal biomass to stimulate methane production in coal seams is a promising low carbon renewable coalbed methane enhancement technique. However, little is known about how the addition of algal biomass amendment affects methane production from coals of different thermal maturity. Here, we show that biogenic methane can be produced from five coals ranging in rank from
Authors
George A. Platt, Katherine J. Davis, Hannah D. Schweitzer, Heidi J. Smith, Matthew W. Fields, Elliott Barnhart, Robin Gerlach