Publications
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Comparison of δ13C analyses of individual foraminifer (Orbulina universa) shells by secondary ion mass spectrometry and gas source mass spectrometry
Rationale: The use of secondary ion mass spectrometry (SIMS) to perform micrometer-scale in situ carbon isotope (δ13C) analyses of shells of marine microfossils called planktic foraminifers holds promise to explore calcification and ecological processes. The potential of this technique, however, cannot be realized without comparison to traditional whole-shell δ13C values measured by gas source mas
Authors
Jody Brae Wycech, Daniel Clay Kelly, Reinhard Kozdon, Akizumi Ishida, Kouki Kitajima, Howard J. Spero, John W. Valley
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
Georectified polygon database of ground-mounted large-scale solar photovoltaic sites in the United States
Over 4,400 large-scale solar photovoltaic (LSPV) facilities operate in the United States as of December 2021, representing more than 60 gigawatts of electric energy capacity. Of these, over 3,900 are ground-mounted LSPV facilities with capacities of 1 MWdc or more. Ground mounted LSPV installations continue increasing, with more than 400 projects appearing online in 2021 alone; however, a comprehe
Authors
Sydny K. Fujita, Zachary H. Ancona, Louisa Kramer, Mary Straka, Tandie E. Gautreau, Dana Robson, Christopher P. Garrity, Ben Hoen, James E. Diffendorfer
Geologic carbon management options for the North Atlantic-Appalachian Region
IntroductionThe U.S. Geological Survey (USGS) North Atlantic-Appalachian Region is developing the regionwide capacity to provide timely science support for decision-makers attempting to enhance carbon removal, sequestration, and emissions mitigation to meet national atmospheric carbon reduction goals. The U.S. Environmental Protection Agency (EPA) reported that in 2021, the fourteen States and the
Authors
Peter D. Warwick, Madalyn S. Blondes, Sean T. Brennan, Steven M. Cahan, C. Özgen Karacan, Kevin D. Kroeger, Matthew D. Merrill
Evaluation of breeding distribution and chronology of North American scoters
North America's scoter species are poorly monitored relative to other waterfowl. Black Melanitta americana, surf M. perspicillata, and white-winged M. deglandi scoter abundance and trend estimates are thus uncertain in many parts of these species' ranges. The most extensive source of waterfowl abundance and distribution data in North America is the Waterfowl breeding population and habitat survey
Authors
Kristin Bianchini, Scott G. Gilliland, Alicia Berlin, Timothy D. Bowman, W. Sean Boyd, Susan E. W. De La Cruz, Daniel Esler, Joseph R. Evenson, Paul L. Flint, Christine Lepage, Scott R. McWilliams, Dustin E. Meattey, Jason E. Osenkowski, Matthew Perry, Jean-François Poulin, Eric T. Reed, Christian Roy, Jean-Pierre L. Savard, Lucas Savoy, Jason L Schamber, Caleb S. Spiegel, John Takekawa, David H. Ward, Mark L. Mallory
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
Machine learning application to assess occurrence and saturations of methane hydrate in marine deposits offshore India
Artificial Neural Networks (ANN) were used to assess methane hydrate occurrence and saturation in marine sediments offshore India. The ANN analysis classifies the gas hydrate occurrence into three types: methane hydrate in pore space, methane hydrate in fractures, or no methane hydrate. Further, predicted saturation characterizes the volume of gas hydrate with respect to the available void volume.
Authors
Leebyn Chong, Timothy Collett, C. Gabriel Creason, Yongkoo Seol, E.M. Myshakin
Canada Basin tectono-sedimentary element, Arctic Ocean
The Canada Basin (CB) formed during a short period of seafloor spreading inferred to be Early Cretaceous in age. Brookian strata of inferred Early Cretaceous–Holocene age comprise the sedimentary fill of the Canada Basin Tectono-Sedimentary Element (CB TSE). Although the CB has remained tectonically quiet since seafloor spreading ceased, both proximal and distal tectonism (Alpha Ridge magmatism, a
Authors
Deborah Hutchinson, David W. Houseknecht, David Mosher
Intramolecular carbon isotope geochemistry of butane isomers from laboratory maturation and Monte-Carlo simulations of kerogen types I, II, and III
Position-specific (PS) carbon isotope compositions of light hydrocarbons such as propane and butane isomers (n-butane and i-butane) can provide a wealth of information on the history of natural gases in the subsurface reservoirs and other environments. For PS carbon isotope analysis of butane isomers, we have established a GC-pyrolysis-GC-isotope ratio mass spectrometry method with demonstrated ac
Authors
Xiaoqiang Li, Hao Xie, Justin E. Birdwell, Gregory McGovern, Juske Horita
Scanning electron microscopic evaluation of broad ion beam milling effects to sedimentary organic matter: Sputter-induced artifacts or naturally occurring porosity?
Research examining organic-matter hosted porosity has significantly increased during the last decade due to greater focus on understanding hydrocarbon migration and storage in source-rock reservoirs, and technological advances in scanning electron microscopy (SEM) capabilities. The examination of nanometer-scale organic-matter hosted porosity by SEM requires the preparation of exceptionally flat g
Authors
Brett J. Valentine, Paul C. Hackley
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
A residual oil zone (ROZ) assessment methodology with application to the central basin platform (Permian Basin, USA) for enhanced oil recovery (EOR) and long-term geologic CO2 storage
Residual oil zones (ROZ) form due to various geologic conditions and are located below the oil/water contact (OWC) of main pay zones (MPZ). Since ROZs usually contain immobile oil, they have not typically been considered commercially attractive for development by conventional primary recovery methods used in the initial phases of oil production. However, during the last decade some operators of th
Authors
C. Özgen Karacan, Sean T. Brennan, Marc L. Buursink, Philip A. Freeman, Celeste D. Lohr, Matthew D. Merrill, Ricardo A. Olea, Peter D. Warwick