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The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
Browse more than 65,000 articles authored by our scientists over the past 100+ year history of the USGS and refine search by topic, location, year, and advanced search.
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Crop type classification, trends, and patterns of central California agricultural fields from 2005 to 2020 Crop type classification, trends, and patterns of central California agricultural fields from 2005 to 2020
California produces many key agricultural products in the United States. Current geospatial agricultural datasets are limited in mapping accuracy, spatial context, or observation period. This study uses machine learning and high-resolution imagery to produce a time series of crop maps to assess crop type trends and patterns across central California from 2005 to 2020. National...
Authors
Britt Windsor Smith, Christopher E. Soulard, Jessica J. Walker
Shallow storage of the explosive Earthquake Flat Pyroclastics magma body, Okataina Volcanic Center, Taupo Volcanic Zone, New Zealand: Evidence from phase-equilibria experiments Shallow storage of the explosive Earthquake Flat Pyroclastics magma body, Okataina Volcanic Center, Taupo Volcanic Zone, New Zealand: Evidence from phase-equilibria experiments
Rhyolitic tuffs range widely in their crystal contents from nearly aphyric to crystal-rich, and their crystal cargoes inform concepts of upper crustal magma reservoirs. The Earthquake Flat pyroclastics (Okataina Volcanic Center, Taupo Volcanic Zone, New Zealand) are 10 km3 of rhyolitic tuffs with abundant (~ 40 vol.%) plagioclase and quartz, minor biotite, hornblende, and orthopyroxene...
Authors
Elizabeth R. G. Grant, Dawnika L. Blatter, Thomas W. Sisson, Kari M Cooper
Collision structures of the Prince William terrane and Chugach terrane docking along the Shumagin and Unimak convergent margins, Alaska, USA Collision structures of the Prince William terrane and Chugach terrane docking along the Shumagin and Unimak convergent margins, Alaska, USA
Western Alaska’s convergent margins are composed of tectonostratigraphic terranes. On land, terrane assembly is recognized along boundaries or sutures between neighboring geologic elements with distinctly different origins. In marine areas where rock outcrops are covered by sediment, recognizing terrane sutures is problematic. A fault in seismic dip line 5 of the ALEUT project has been...
Authors
Roland E. von Huene, John J. Miller
Host jump of an exotic fish rhabdovirus into a new class of animals poses a disease threat to amphibians Host jump of an exotic fish rhabdovirus into a new class of animals poses a disease threat to amphibians
Spring viremia of carp virus (SVCV) is a rhabdovirus that primarily infects cyprinid finfishes and causes a disease notifiable to the World Organization for Animal Health. Amphibians, which are sympatric with cyprinids in freshwater ecosystems, are considered non-permissive hosts of rhabdoviruses. The potential host range expansion of SVCV in an atypical host species was evaluated by...
Authors
Eveline J. Emmenegger, Emma K. Bueren, Carla M. Conway, George E. Sanders, A. Noble Hendrix, Tamara Schroeder, Emiliano Di Cicco, Phuc H. Pham, Lumsden John S., Sharon C. Clouthier
Assessing the population consequences of disturbance and climate change for the Pacific walrus Assessing the population consequences of disturbance and climate change for the Pacific walrus
Climate change and anthropogenic disturbance are increasingly affecting wildlife at a global scale. Predicting how varying types and degrees of disturbance may interact to influence population dynamics is a key management challenge. Population consequences of disturbance (PCoD) models provide a framework to link effects of anthropogenic disturbance on an individual’s behavior and...
Authors
Devin L. Johnson, Joseph Michael Eisaguirre, Rebecca L. Taylor, Joel L. Garlich-Miller
Potential for spatial coexistence of a transboundary migratory species and wind energy development Potential for spatial coexistence of a transboundary migratory species and wind energy development
Global expansion in wind energy development is a notable achievement of the international community’s effort to reduce carbon emissions during energy production. However, the increasing number of wind turbines have unintended consequences for migratory birds and bats. Wind turbine curtailment and other mitigation strategies can reduce fatalities, but improved spatial and temporal data...
Authors
Ta-Ken Huang, Xiao Feng, Jonathan J. Derbridge, Kaitlin Libby, James E. Diffendorfer, Wayne E. Thogmartin, Gary McCracken, Rodrigo Medellin, Laura Lopez-Hoffman
Photogrammetry of the deep seafloor from archived unmanned submersible exploration dives Photogrammetry of the deep seafloor from archived unmanned submersible exploration dives
Large amounts of video images have been collected for decades by scientific and governmental organizations in deep (>1000 m) water using manned and unmanned submersibles and towed cameras. The collected images were analyzed individually or were mosaiced in small areas with great effort. Here, we provide a workflow for utilizing modern photogrammetry to construct virtual geological...
Authors
Claudia Flores, Uri S. ten Brink
Gape-limited invasive predator frequently kills avian prey that are too large to swallow Gape-limited invasive predator frequently kills avian prey that are too large to swallow
Gape-limited predators (e.g., snakes, many fish) are not generally expected to pose a predation threat to prey that are too large for them to swallow. However, the extent to which snakes predate on prey that exceed their gape limitation remains largely unknown. We conducted the first study to investigate the influence of both prey and predator sizes on the frequency of ingestion success...
Authors
Martin Kastner, Scott Michael Goetz, Kayla M Baker, Shane R. Siers, Eben H. Paxton, Melia Gail Nafus, Haldre Rogers
Evaluating mountain lion diet before and after a removal of feral horses in a semiarid environment Evaluating mountain lion diet before and after a removal of feral horses in a semiarid environment
Non-native species can affect ecosystems by influencing native predator-prey dynamics. Therefore, management interventions designed to remove non-natives may inadvertently lead to increased predation on native species. Feral horses are widely distributed throughout the arid parts of western North America. A growing body of research indicates that horses can be an important prey species...
Authors
Peter C. Iacono, Kathryn A. Schoenecker, Kezia R. Manlove, Pat J. Jackson, David C. Stoner
Cathodoluminescence imaging and spectrometry of a jadeite microbeam reference crystal: Detection of Ce3+ Cathodoluminescence imaging and spectrometry of a jadeite microbeam reference crystal: Detection of Ce3+
Options for selecting a high Na concentration mineral for instrument calibration that are suitably stable under the electron beam are limited [1]. NaCl (approximately a mass fraction of 39 % Na) is not practical for use alongside other embedded and polished materials in a mounted block of standards. While albite (NaAlSi3O8; approximately a mass fraction of 8 % Na) represents a typical...
Authors
Thomas Lameris, Heather A. Lowers, Scott A. Wight, Edward P. Vicenzi
Correlating quantified cathodoluminescence spectra in jadeite with micro-scale color measurements in visible-near infrared reflectance spectrometry Correlating quantified cathodoluminescence spectra in jadeite with micro-scale color measurements in visible-near infrared reflectance spectrometry
Cultures throughout history have valued jadeite jade (hereinafter jade), a natural material assemblage composed predominately of the NaAl endmember pyroxene, jadeite (NaAlSi2O6) that is prized for its mechanical properties and enticing coloration [1, 2]. The geological setting for the formation of jadeite-rich rocks and associated complex geochemical phenomena is well documented in the...
Authors
Edward P. Vicenzi, Thomas Lameris, Heather A. Lowers, Colin MacRae
Compositional and structural mapping of Northwest Africa 15507 angrite Compositional and structural mapping of Northwest Africa 15507 angrite
Angrite meteorites represent interesting sampling of planetary crustal environments. Quench-textured angrites with strong crystal zoning originated from the shallow surface region, with evidence of reducing conditions during solidification. Plutonic angrites have more coarse-grained igneous and metamorphic textures with comparatively less zoning and are interpreted as having equilibrated...
Authors
Heather A. Lowers, Paul C. Carpenter, Jay M. Thompson, Anthony Irving