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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

Interlaboratory study: Testing reproducibility of solid biofuels component identification using reflected light microscopy

Considering global market trends and concerns about climate change and sustainability, increased biomass use for energy is expected to continue. As more diverse materials are being utilized to manufacture solid biomass fuels, it is critical to implement quality assessment methods to analyze these fuels thoroughly. One such method is reflected light microscopy (RLM), which has the potential to comp
Authors
Agnieszka Drobniak, Maria Mastalerz, Zbigniew Jelonek, Iwona Jelonek, Tushar Adsul, Neža Malenšek Andolšek, Omid Haeri Ardakani, Tara Congo, Batbold Demberelsuren, Bryon S. Donohoe, Ashley Douds, Deolinda Flores, Ranjin Ganzorig, Santanu Ghosh, Andrew Gize, Paula Alexandra Goncalves, Paul C. Hackley, Javin J. Hatcherian, James C. Hower, Stavros Kalaitzidis, Sławomir Kędzior, Wayne Knowles, Jolanta Kus, Kacper Lis, Grzegorz Lis, Bei Liu, Qingyong Luo, Meili Du, Divya Mishra, Magdalena Misz-Kennan, Theophile Mugerwa, Jennifer Nedzweckas, Jennifer M. K. O'Keefe, Jackie Park, Richard Pearson, Henrik I. Petersen, Julito Reyes, Joana Ribeiro, Genaro de la Rosa-Rodriguez, Piotr Sosnowski, Brett J. Valentine, Atul Kumar Varma, Małgorzata Wojtaszek-Kalaitzidi, Zhanjie Xu, Alexander Zdravkov, Konrad Ziemianin

Geology and assessment of coal resources for the Cherokee coal bed in the Fort Union Formation, south-central Wyoming

The Cherokee coal bed is a locally thick and laterally continuous coal bed in the Overland Member of the Paleocene Fort Union Formation in south-central Wyoming. It represents a significant resource that is easily accessible and may be extractable through both surface and underground mining methods. A database of more than 600 data points, comprising coalbed methane wells, coal exploration drill h
Authors
Brian N. Shaffer, Ricardo A. Olea

Assessment of continuous oil and gas resources in the Upper Jurassic Smackover Formation of the onshore U.S. Gulf Coast, 2022

Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean continuous resources of 0.8 billion barrels of oil and 16 trillion cubic feet of gas in the Upper Jurassic Smackover Formation of the onshore U.S. Gulf Coast region.

Authors
Katherine J. Whidden, Justin E. Birdwell, Rand D. Gardner, Scott A. Kinney, Stanley T. Paxton, Janet K. Pitman, Christopher J. Schenk

Merging machine learning and geostatistical approaches for spatial modeling of geoenergy resources

Geostatistics is the most commonly used probabilistic approach for modeling earth systems, including quality parameters of various geoenergy resources. In geostatistics, estimates, either on a point or block support, are generated as a spatially-weighted average of surrounding samples. The optimal weights are determined through the stationary variogram model which accounts for the spatial structur
Authors
Gamze Erdogan Erten, Oktay Erten, C. Özgen Karacan, Jeff Boisvert, Clayton V. Deutsch