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Fluorine-rich mafic lower crust in the southern Rocky Mountains: The role of pre-enrichment in generating fluorine-rich silicic magmas and porphyry Mo deposits

Fluorine-rich granites and rhyolites occur throughout the southern Rocky Mountains, but the origin of F-enrichment has remained unclear. We test if F-enrichment could be inherited from ancient mafic lower crust by: (1) measuring amphibole compositions, including F and Cl contents, of lower crustal mafic granulite xenoliths from northern Colorado to determine if they are unusually enriched in halog
Joshua Mark Rosera, Ryan Edward Frazer, Ryan D. Mills, Kristin Jacob, Sean P. Gaynor, Drew S. Coleman, G. Lang Farmer

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

Guidelines for calibration of uncrewed aircraft systems imagery

Executive SummaryThis report outlines quality assurance (QA) processes, including radiometric and geometric calibration guidelines, and guidelines for data acquisition and quality control to be followed by U.S. Geological Survey (USGS) researchers for acquiring and processing uncrewed aircraft systems (UAS) data. These QA processes ensure that UAS data can be used for quantitative analysis and are
Aparajithan Sampath, Mahesh Shrestha, Michelle While, Victoria Mary Scholl

Triple oxygen isotope compositions of globally distributed soil carbonates record widespread evaporation of soil waters

The stable isotopic composition of pedogenic carbonates is central to many studies of past climate and topography, providing a basis for our understanding of Earth's terrestrial history. A core assumption of many applications of oxygen isotope values (δ18O) of pedogenic carbonate is that they reflect the δ18O value of precipitation (rain/snow). This assumption is violated if soil carbonates form i
Julia Kelson, Tyler E. Huth, Benjamin H. Passey, Naomi E. Levin, Sierra V. Petersen, Paolo Ballato, Emily J. Beverly, Daniel O. Breecker, Gregory D. Hoke, Adam M. Hudson, Ji Haoyuan, Alexis Licht, Jay Quade

U.S. Geological Survey Rocky Mountain Region 2022 science exchange, showcasing interdisciplinary and state-of-the-art USGS science

IntroductionThe Rocky Mountains and the Colorado River Basin in the Western United States represent complex, interconnected systems that sustain a number of species, including tens of millions of humans. These systems face several challenges, including worsening drought, altered wildfire regimes, climate change, and the spread of invasive species. These factors can exacerbate one another, further
Dana E. Peterson, Katherine L. French, Jeannette H. Oden, Patrick J. Anderson, Timothy N. Titus, Katharine G. Dahm, Jessica M. Driscoll, William J. Andrews

Monazite and xenotime petrochronologic constraints on four Proterozoic tectonic episodes and ca. 1705 Ma age of the Uncompahgre Formation, southwestern Colorado, USA

The Proterozoic tectonic evolution of the south-western USA remains incompletely understood due to limited constraints on the timing and conditions of the tectono-metamorphic phases and depositional age of metasedimentary successions. We integrated multi-scale compositional mapping, petrologic modeling, and in situ geochronology to constrain pressure-temperature-time paths from samples of Paleopro
Ian William Hillenbrand, Michael L. Williams, Karl E. Karlstrom, Amy K. Gilmer, Heather A. Lowers, Michael J. Jercinovic, Kaitlyn Suarez, Amanda (Kate) Souders

Quantification of wetland vegetation communities features with airborne AVIRIS-NG, UAVSAR, and UAV LiDAR data in Peace-Athabasca Delta

Arctic-boreal wetlands, important ecosystems for biodiversity and ecological services, are experiencing hydrological changes including permafrost thaw, earlier snowmelt, and increased wildfire susceptibility. These changes are affecting wetland productivity, species diversity, and biogeochemical cycles. However, given the diverse forms and structures of wetland vegetation communities, traditional
Chao Wang, Tamlin M. Pavelsky, Ethan D. Kyzviat, Fenix Garcia-Tigreros, Erika Podest, Fangfang Yao, Xiao Yang, Shuai Zhang, Conghe Song, Theodore Langhorst, Wayana Dolan, Martin R. Kurek, Merritt E. Harlan, Laurence C. Smith, David Butman, Robert G.M. Spencer, Colin J. Gleason, Kimberly Wickland, Robert G. Striegl, Daniel L. Peters

Pliocene–Pleistocene hydrology and pluvial lake during Marine Isotope Stages 5a and 4, Deep Springs Valley, western Great Basin, Inyo County, California

Deep Springs Valley (DSV) is a hydrologically isolated valley between the White and Inyo mountains that is commonly excluded from regional paleohydrology and paleoclimatology. Previous studies showed that uplift of Deep Springs ridge (informal name) by the Deep Springs fault defeated streams crossing DSV and hydrologically isolated the valley sometime after eruption of the Pleistocene Bishop Tuff
Jeffrey R. Knott, Shannon A. Mahan, Jordan E. Bright, Lindsey Langer, Adam Ramirez, Kyle McCarty, Anna L. Garcia

The role of lithology and climate on bedrock river incision and terrace development along the Buffalo National River, Arkansas

The Buffalo National River in northwest Arkansas preserves an extensive Quaternary record of fluvial bedrock incision and aggradation across lithologies of variable resistance. In this work, we apply optically stimulated luminescence (OSL) dating to strath and fill terraces along the Buffalo River to elucidate the role of lithology and climate on the development of the two youngest terrace units (
Kathleen Rodrigues, Amanda Keen-Zebert, Stephanie Shepherd, Mark R. Hudson, Charles J. Bitting, Bradley G. Johnson, Abigail Langston

High voltage: The molecular properties of redox-active dissolved organic matter in northern high-latitude lakes

Redox-active functional groups in dissolved organic matter (DOM) are crucial for microbial electron transfer and methane emissions. However, the extent of aquatic DOM redox properties across northern high-latitude lakes and their relationships with DOM composition have not been thoroughly described. We quantified electron donating capacity (EDC) and electron accepting capacity (EAC) in lake DOM fr
Martin R. Kurek, Fenix Garcia-Tigreros, Natalie A. Nichols, Gregory K. Druschel, Kimberly Wickland, Mark M. Dornblaser, Robert G. Striegl, Sydney F. Niles, Amy M. McKenna, Pieter J.K Aukes, Ethan D. Kyzviat, Chao Wang, Laurence C. Smith, Sherry L. Schiff, David Butman, Robert G.M. Spencer

Paleohydrologic history of pluvial lake San Agustin, New Mexico: Tracking changing effective moisture in southwest North America through the last glacial transition

Paleoclimate records across the Intermountain West region of North America show significant regional variation in timing and magnitude of wet conditions that accompanied the last glacial-interglacial transition. To understand the climate controls on paleohydrologic change, well-dated records are needed across the region. The Plains of San Agustin (New Mexico, USA) is a closed-basin watershed of th
Adam M. Hudson, Jay Quade, Vance T. Holliday, Brendan Fenerty, Jordon Bright, Harrison J. Gray, Shannon A. Mahan

The extent of buildings in wildland vegetation of the conterminous U.S. and the potential for conservation in and near National Forest private inholdings

Development in natural areas is a leading threat to biodiversity. Global conservationists have called for the expansion of protected areas to preserve wildlands that are free from buildings, and in the U.S., the ‘America the Beautiful’ initiative aims to protect 30% of land and water areas by 2030 (known as the ‘30x30’ target). Here, we determined opportunities and limitations for conservation in
Amanda R. Carlson, Volker C. Radeloff, Dave P. Helmers, Miranda H. Mockrin, Todd Hawbaker, Anna M. Pidgeon