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Independent age estimates resolve the controversy of ancient human footprints at White Sands Independent age estimates resolve the controversy of ancient human footprints at White Sands

Human footprints at White Sands National Park, New Mexico, USA, reportedly date to between ~23,000 and 21,000 years ago according to radiocarbon dating of seeds from the aquatic plant Ruppia cirrhosa. These ages remain controversial because of potential old carbon reservoir effects that could compromise their accuracy. We present new calibrated 14C ages of terrestrial pollen collected...
Authors
Jeffrey S. Pigati, Kathleen B. Springer, Jeffrey S. Honke, David Wahl, Marie Rhondelle Champagne, Susan R.H. Zimmerman, Harrison J. Gray, Vincent L. Santucci, Daniel Odess, David Bustos, Matthew R. Bennett

Geochemical evidence for evolving Proterozoic crustal thickness and orogenic styles in southwestern Laurentia Geochemical evidence for evolving Proterozoic crustal thickness and orogenic styles in southwestern Laurentia

It has long been challenging for researchers to track the crustal thickness and mode(s) of crustal modification in ancient convergent margins, limiting evaluation of the tectonic styles and processes that modify continental crust during orogenesis. We present trace element igneous geochemical crustal thickness proxies that quantitatively track the crustal thickness evolution of the long...
Authors
Ian William Hillenbrand, Karl E. Karlstrom, Michael L. Williams, Amy K. Gilmer, Wayne R. Premo, Peter B Davis

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 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...
Authors
Joshua Mark Rosera, Ryan Edward Frazer, Ryan D. Mills, Kristin Jacob, Sean P. Gaynor, Drew S. Coleman, G. Lang Farmer

Potential economic consequences along migratory flyways from reductions in breeding habitat of migratory waterbirds Potential economic consequences along migratory flyways from reductions in breeding habitat of migratory waterbirds

The migration of species, often across continents, makes it difficult to quantify the cumulative effects of local- and regional-scale conservation actions. Further, variation in stakeholder interests, differing jurisdictional governance processes, priorities, and monitoring abilities across the migratory range shapes place-specific differences in management actions. These differences may...
Authors
Wayne E. Thogmartin, James H. Devries, Darius J. Semmens, James E. Diffendorfer, James A. Dubovksy, Jonathan J. Derbridge, Brady J. Mattsson

Banking on strong rural livelihoods and the sustainable use of natural capital in post-conflict Colombia Banking on strong rural livelihoods and the sustainable use of natural capital in post-conflict Colombia

In post-conflict Colombia, the government has prioritized resettlement of displaced people through development of strong rural livelihoods and the sustainable use of natural capital. In this paper, we considered government proposals for expanding payment for ecosystem services (PES) and sustainable silvopastoral systems, and private-sector investment in habitat banking. We coupled the...
Authors
Onil Banerjee, Martin Cicoweiz, Ziga Malek, Peter H. Verburg, Renato Vargas, Sean Goodwin, Kenneth J. Bagstad, Josue Avila Murillo

Predicting burn severity for integration with post-fire debris-flow hazard assessment: A case study from the Upper Colorado River Basin, USA Predicting burn severity for integration with post-fire debris-flow hazard assessment: A case study from the Upper Colorado River Basin, USA

Background: Burn severity significantly increases the likelihood and volume of post-wildfire debris flows. Pre-fire severity predictions can expedite mitigation efforts because precipitation contributing to these hazards often occurs shortly after wildfires, leaving little time for post-fire planning and management. Aim: The aim of this study was to predict burn severity using pre-fire...
Authors
Adam Gerhard Wells, Todd Hawbaker, John Kevin Hiers, Jason W. Kean, Rachel A. Loehman, Paul F. Steblein

Guidelines for calibration of uncrewed aircraft systems imagery Guidelines for calibration of uncrewed aircraft systems imagery

Executive Summary This 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...
Authors
Aparajithan Sampath, Mahesh Shrestha, Michelle While, Victoria Mary Scholl

The global wildland-urban interface The global wildland-urban interface

The wildland–urban interface (WUI) is where buildings and wildland vegetation meet or intermingle. It is where human–environmental conflicts and risks can be concentrated, including the loss of houses and lives to wildfire, habitat loss and fragmentation and the spread of zoonotic diseases. However, a global analysis of the WUI has been lacking. Here, we present a global map of the 2020...
Authors
F. Schug, Avi Bar-Massada, Amanda Renee Carlson, H. Cox, Todd Hawbaker, D. Helmers, Patrick Hostert, D. Kaim, Neda K. Kasraee, S. Martinuzzi, Miranda H. Mockrin, Kira A. Pfoch, Volker C. Radeloff

Triple oxygen isotope compositions of globally distributed soil carbonates record widespread evaporation of soil waters 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...
Authors
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 U.S. Geological Survey Rocky Mountain Region 2022 science exchange, showcasing interdisciplinary and state-of-the-art USGS science

Introduction The 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...
Authors
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 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...
Authors
Ian William Hillenbrand, Michael L. Williams, Karl E. Karlstrom, Amy K. Gilmer, Heather A. Lowers, Michael J. Jercinovic, Kaitlyn Suarez, Amanda Souders

Tracing magmatic genesis and evolution through single zircon crystals from successive supereruptions from the Socorro Caldera Complex, USA Tracing magmatic genesis and evolution through single zircon crystals from successive supereruptions from the Socorro Caldera Complex, USA

Large volume rhyolitic ignimbrite volcanism is a significant contributor to the evolving crust. The introduction of high-silica material into the upper crust, differentiation within the middle crust, and partial melting in the lower crust contributes to geochemical and isotopic evolution of the crust. Developing accurate models for the genetic evolution of these events is dependent upon
Authors
Sean P. Gaynor, Tyson Michael Smith, Urs Schaltegger
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