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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

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