Publications
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Oxygen isotopes of land snail shells in high latitude regions
The present study investigates the environmental significance of the oxygen isotopic composition of several modern land snail species collected along two north-to-south transects in Alaska and Scandinavia at latitudes between 60 and 70 °N. We tested the hypothesis that land snail shell δ18O values primarily track precipitation δ18O. The results show that shell δ18O values from Scandinavia were ∼5.
Authors
Catherine Nield, Yurena Yanes, Jeffrey S. Pigati, Jason A. Rech, Ted von Proschwitz, Jeffrey C. Nekola
Photomosaics and logs associated with study of West Napa Fault at Ehlers Lane, north of Saint Helena, California
The West Napa Fault has previously been mapped as extending ~45 kilometers (km) from northern Vallejo to southern Saint Helena, California, dominantly running along the western edge of Napa Valley. A zone of fault strands (some previously unmapped) along a ~15-km section of the fault ruptured during the 2014 magnitude 6.0 South Napa earthquake, illustrating the need for further investigation of th
Authors
Belle E. Philibosian, Robert R. Sickler, Carol S. Prentice, Alexandra J. Pickering, Patrick Gannon, Kiara N. Broudy, Shannon A. Mahan, Jazmine N. Titular, Eli A. Turner, Cameron Folmar, Sierra F. Patterson, Emilie E. Bowman
Major reorganization of the Snake River modulated by passage of the Yellowstone Hotspot
The details and mechanisms for Neogene river reorganization in the U.S. Pacific Northwest and northern Rocky Mountains have been debated for over a century with key implications for how tectonic and volcanic systems modulate topographic development. To evaluate paleo-drainage networks, we produced an expansive data set and provenance analysis of detrital zircon U-Pb ages from Miocene to Pleistocen
Authors
Lydia M. Staisch, Jim E. O'Connor, Charles M. Cannon, Christopher Holm-Denoma, Paul K. Link, John Lasher, Jeremy A. Alexander
Response to comment on “Evidence of humans in North America during the Last Glacial Maximum”
Madsen et al. question the reliability of calibrated radiocarbon ages associated with human footprints discovered recently in White Sands National Park, New Mexico, USA. On the basis of the geologic, hydrologic, stratigraphic, and chronologic evidence, we maintain that the ages are robust and conclude that the footprints date to between ~23,000 and 21,000 years ago.Madsen et al. (1) question the v
Authors
Jeffrey S. Pigati, Kathleen B. Springer, Matthew R. Bennett, David Bustos, Thomas M. Urban, Vance T. Holliday, Sally C. Reynolds, Daniel Odess
From crystals to crustal-scale seismic anisotropy: Bridging the gap between rocks and seismic studies with digital geologic map data in Colorado
Deep continental crustal structures are enigmatic due to lack of direct exposures and limited tools to investigate them remotely. Seismic waves can sample these rocks, but most seismic methods focus on coarse crustal structures while laboratory measurements concentrate on crystal-scale rock properties, and little work has been conducted to bridge this interpretation gap. In some places, geologic m
Authors
Michael G. Frothingham, Kevin H. Mahan, Vera Schulte-Pelkum, Jonathan Caine, Frederick W. Vollmer
Mesilla / Conejos-Médanos Basin: U.S.-Mexico transboundary water resources and research needs
Synthesizing binational data to characterize shared water resources is critical to informing binational management. This work uses binational hydrogeology and water resource data in the Mesilla/Conejos-Médanos Basin (Basin) to describe the hydrologic conceptual model and identify potential research that could help inform sustainable management. The Basin aquifer is primarily composed of continuous
Authors
Andrew J. Robertson, Anne-Marie Matherne, Jeff D. Pepin, Andre B. Ritchie, Donald S. Sweetkind, Andrew Teeple, Alfredo Granados Olivas, Ana Cristina García Vásquez, Kenneth C. Carroll, Erek H. Fuchs, Amy E. Galanter
Coastal paleogeography of the Pacific Northwest, USA, for the last 12,000 years accounting for three-dimensional earth structure
Predictive modeling of submerged archaeological sites requires accurate sea-level predictions in order to reconstruct coastal paleogeography and associated geographic features that may have influenced the locations of occupation sites such as rivers and embayments. Earlier reconstructions of the paleogeography of parts of the western U.S. coast used an assumption of eustatic sea level, but this ne
Authors
Jorie Clark, Jay R. Alder, Marisa Borreggine, Jerry X Mitrovica, Konstantin Latychev
Evolution and taxonomy of the Paleogene calcareous nannofossil genus Hornibrookina
The genus Hornibrookina consists of enigmatic calcareous nannofossils that first appeared shortly after the K-Pg mass extinction. Due to their relative paucity in most published sections, specimens of this genus have not been previously studied in detail and their paleobiogeographic preferences and evolutionary history have been poorly understood. Biostratigraphic and morphometric analyses of Horn
Authors
Jean Self-Trail, David K. Watkins, James J. Pospichal, Ellen Seefelt
Paleohydrological context for recent floods and droughts in the Fraser River Basin, British Columbia, Canada
The recent intensification of floods and droughts in the Fraser River Basin (FRB) of British Columbia has had profound cultural, ecological, and economic impacts that are expected to be exacerbated further by anthropogenic climate change. In part due to short instrumental runoff records, the long-term stationarity of hydroclimatic extremes in this major North American watershed remains poorly unde
Authors
Rebecca Lynn Brice, Bethany Coulthard, Inga Homfeld, Laura Dye, Kevin Anchukaitis
Estimating the pelagic ocean’s benefits to humanity can enhance ocean governance
The human footprint on the global ocean is ever-increasing, particularly with new ways to grow food in the ocean, new technologies in marine energy production as a way to resolve climate change, and transport and commerce expanding across the ocean. Yet, human activities in the ocean have long been managed using a sectoral approach (e.g., fisheries, biodiversity protection, energy production, ship
Authors
Lida Teneva, Aaron L. Strong, Vera Agostini, Kenneth J. Bagstad, Evangelina G Drakou, Zachary H. Ancona, Kristina Gjerde, Andrew C Hume, Nicholas Jickling
Beyond bulk: Density fractions explain heterogeneity in global soil carbon abundance and persistence
Understanding the controls on the amount and persistence of soil organic carbon (C) is essential for predicting its sensitivity to global change. The response may depend on whether C is unprotected, isolated within aggregates, or protected from decomposition by mineral associations. Here, we present a global synthesis of the relative influence of environmental factors on soil organic C partitionin
Authors
Katherine Heckman, Caitlin E. Hicks Pries, Corey Lawrence, Craig Rasmussen, Susan E. Crow, Alison M. Hoyt, Sophie F. von Fromm, Zheng Shi, Shane Stoner, Casey McGrath, Jeffery Beem-Miller, Asmeret Asefaw Berhe, Joseph C. Blankinship, Marco Keiluweit, Erika Marín-Spiotta, J. Grey Monroe, Alain F. Plante, Joshua Schimel, Carlos A. Sierra, Aaron Thompson, Rota Wagai
Social Values for Ecosystem Services (SolVES): Open-source spatial modeling of cultural services
Social Values for Ecosystem Services (SolVES) version 4.0 is a fully open-source, GIS-based tool designed to aid in the creation of quantitative, spatially explicit models of the nonmonetary values attributed to cultural ecosystem services, such as aesthetics and recreation, specifically to facilitate their incorporation into larger ecosystem service assessments. Newly redeveloped for QGIS, SolVES
Authors
Benson C. Sherrouse, Darius J. Semmens, Zachary H. Ancona