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Articles 1 - 30 of 59
Full-Text Articles in Geology
One Health In Action: Flea Control And Interpretative Education At Badlands National Park, David Eads, Lindsey Buehler, Anne Esbenshade, Jason Fly, Evan Miller, Holly Redmond, Emily Ritter, National Park Service, Sasha Wittmann, Paul Roghair, Eddie Childers
One Health In Action: Flea Control And Interpretative Education At Badlands National Park, David Eads, Lindsey Buehler, Anne Esbenshade, Jason Fly, Evan Miller, Holly Redmond, Emily Ritter, National Park Service, Sasha Wittmann, Paul Roghair, Eddie Childers
United States Geological Survey: Staff Publications
No abstract provided.
Do Pharmaceuticals In The Environment Pose A Risk To Wildlife?, Thomas G. Bean, Elizabeth A. Chadwick, Marta Herrero‐Villar, Rafael Mateo, Vinny Naidoo, Barnett A. Rattner
Do Pharmaceuticals In The Environment Pose A Risk To Wildlife?, Thomas G. Bean, Elizabeth A. Chadwick, Marta Herrero‐Villar, Rafael Mateo, Vinny Naidoo, Barnett A. Rattner
United States Geological Survey: Staff Publications
The vast majority of knowledge related to the question “To what extent do pharmaceuticals in the environment pose a risk to wildlife?” stems from the Asian vulture crisis (>99% decline of some species of Old World vultures on the Indian subcontinent related to the veterinary use of the nonsteroidal anti‐inflammatory drug [NSAID] diclofenac). The hazard of diclofenac and other NSAIDs (carprofen, flunixin, ketoprofen, nimesulide, phenylbutazone) to vultures and other avian species has since been demonstrated; indeed, only meloxicam and tolfenamic acid have been found to be vulture‐safe. Since diclofenac was approved for veterinary use in Spain and Italy in …
A 14,100 Cal B. P. Rocky Mountain Locust Cache From Winnemucca Lake, Pershing County, Nevada, Evan J. Pellegrini, Eugene M. Hattori, Larry Benson, John Southon, Hojun Song, Derek A. Woller
A 14,100 Cal B. P. Rocky Mountain Locust Cache From Winnemucca Lake, Pershing County, Nevada, Evan J. Pellegrini, Eugene M. Hattori, Larry Benson, John Southon, Hojun Song, Derek A. Woller
United States Geological Survey: Staff Publications
The remains of approximately 1000 (MNI) Rocky Mountain locusts (Melanoplus spretus) from an archaeological cache pit in Crypt Cave, Winnemucca (dry) Lake, Nevada, date to between 14,305–14,067 calendar years before present (95.4 % confidence; 12,238 ± 18 14C yrs. B.P.). The age of this western Great Basin occupation along the shoreline of Lake Lahontan is consistent with occupation of several other Western North American terminal Pleistocene sites dating prior to 14,000 cal. B.P., including distinctive petroglyphs on the western shore of Winnemucca Lake dating as early as 14,800–13,200 cal. B.P.
Comparative Behavioral Ecotoxicology Of Inland Silverside Larvae Exposed To Pyrethroids Across A Salinity Gradient, Sara J. Hutton, Samreen Siddiqui, Emily I. Pedersen, Christopher Y. Markgraf, Amelie Segarra, Michelle L. Hladik, Richard E. Connon, Susanne M. Brander
Comparative Behavioral Ecotoxicology Of Inland Silverside Larvae Exposed To Pyrethroids Across A Salinity Gradient, Sara J. Hutton, Samreen Siddiqui, Emily I. Pedersen, Christopher Y. Markgraf, Amelie Segarra, Michelle L. Hladik, Richard E. Connon, Susanne M. Brander
United States Geological Survey: Staff Publications
Pyrethroids, a class of commonly used insecticides, are frequently detected in aquatic environments, including estuaries. The influence that salinity has on organism physiology and the partitioning of hydrophobic chemicals, such as pyrethroids, has driven interest in how toxicity changes in saltwater compared to freshwater. Early life exposures in fish to pyrethroids cause toxicity at environmentally relevant concentrations, which can alter behavior. Behavior is a highly sensitive endpoint that influences overall organism fitness and can be used to detect toxicity of environmentally relevant concentrations of aquatic pollutants. Inland Silversides (Menidia beryllina), a commonly used euryhaline model fish species, were exposed …
Using Active Source Seismology To Image The Palos Verdes Fault Damage Zone As A Function Of Distance, Depth, And Geology, Travis Alongi, Emily E. Brodsky, Jared Kluesner, Daniel Brothers
Using Active Source Seismology To Image The Palos Verdes Fault Damage Zone As A Function Of Distance, Depth, And Geology, Travis Alongi, Emily E. Brodsky, Jared Kluesner, Daniel Brothers
United States Geological Survey: Staff Publications
Fault damage zones provide a window into the non-elastic processes of an earthquake. Geological and seismic tomography methods have been unable to measure damage zones at depth with sufficient spatial sampling to evaluate the relative influence of depth, distance, and lithological variations. Here, we identify and analyze the damage zone of the Palos Verdes Fault offshore southern California using two 3D seismic reflection datasets. We apply a novel algorithm to identify discontinuities attributed to faults and fractures in large seismic volumes and examine the spatial distribution of fault damage in sedimentary rock surrounding the Palos Verdes Fault. Our results show …
Coastal Wetland Area Change For Two Freshwater Diversions In The Mississippi River Delta, John R. White, Brady Couvillion, John W. Day
Coastal Wetland Area Change For Two Freshwater Diversions In The Mississippi River Delta, John R. White, Brady Couvillion, John W. Day
United States Geological Survey: Staff Publications
Coastal systems around the globe are being re-integrated with adjacent river systems to restore the natural hydrologic connection to riparian wetlands. The Mississippi River sediment diversions or river reconnections are one such tool to combat high rates of wetland loss in coastal Louisiana, USA by providing freshwater, sediment, and nutrients. There has been some disagreement in the published literature whether re-establishing river reconnection is slowing or contributing to coastal wetland loss. This issue is due to the difficulties in the application of remote sensing in low-relief environments where water level changes could indicate either land loss or simply temporary submergence. …
Evidence For The ~ 1.4 Ga Picuris Orogeny In The Central Colorado Front Range, Asha A. Mahatma, Yvette D. Kuiper, Christopher S. Holm-Denoma
Evidence For The ~ 1.4 Ga Picuris Orogeny In The Central Colorado Front Range, Asha A. Mahatma, Yvette D. Kuiper, Christopher S. Holm-Denoma
United States Geological Survey: Staff Publications
We present the first evidence for sedimentation and new evidence for penetrative deformation and metamorphism in the central Colorado Front Range associated with the ~ 1.48–1.35 Ga Picuris orogeny. This orogeny has recently been recognized in New Mexico, Arizona and southern Colorado and may be part of a larger active accretionary margin that includes the ~ 1.51–1.46 Ga Pinware and Baraboo events, in eastern Canada and central US respectively, that preceded the amalgamation of the Rodinian supercontinent. We demonstrate that in addition to ~ 1.4 Ga reactivation of northeast-trending Paleoproterozoic shear zones, regional folding occurred in an area south of …
Level And Pattern Of Overstory Retention Shape The Abundance And Long-Term Dynamics Of Natural And Created Snags, Charles B. Halpern, Allison K. Rossman, Joan C. Hagar
Level And Pattern Of Overstory Retention Shape The Abundance And Long-Term Dynamics Of Natural And Created Snags, Charles B. Halpern, Allison K. Rossman, Joan C. Hagar
United States Geological Survey: Staff Publications
Standing dead trees, or snags, serve myriad functions in natural forests, but are often scarce in forests managed for timber production. Variable retention (VR), the retention of live and dead trees through harvest, has been adopted globally as a less intensive form of regeneration harvest. In this study, we explore how two key elements of VR systems — level (amount) and spatial pattern of live-tree retention — affect the carryover and post-harvest dynamics of natural and artificially created snags. We present nearly two decades of data from the DEMO Study, a regional-scale experiment in VR harvests of Douglas-fir-dominated forests in …
Hydrogen Isotope Behavior During Rhyolite Glass Hydration Under Hydrothermal Conditions, Michael R. Hudak, Ilya N. Bindeman, James M. Watkins, Jacob B. Lowenstern
Hydrogen Isotope Behavior During Rhyolite Glass Hydration Under Hydrothermal Conditions, Michael R. Hudak, Ilya N. Bindeman, James M. Watkins, Jacob B. Lowenstern
United States Geological Survey: Staff Publications
The diffusion of molecular water (H2Om) from the environment into volcanic glass can hydrate the glass up to several wt% at low temperature over long timescales. During this process, the water imprints its hydrogen isotope composition (δDH2O) to the glass (δDgl) offset by a glass-H2O fractionation factor (ΔDgl-H2O = δDgl – δDH2O) which is approximately -33‰ at Earth surface temperatures. Glasses hydrate much more rapidly at higher, sub-magmatic temperatures as they interact with H2O during eruption, transport, and emplacement. To aid in the interpretation …
Soils Of The Central Nebraska Loess Hills And Central Loess Plains, Judith Turk, Rebecca Young, Nicolas A. Jelinsky, Amber D. Anderson, Ashlee Dere, Colby J. Moorberg, Rachel K. Owen
Soils Of The Central Nebraska Loess Hills And Central Loess Plains, Judith Turk, Rebecca Young, Nicolas A. Jelinsky, Amber D. Anderson, Ashlee Dere, Colby J. Moorberg, Rachel K. Owen
Conservation and Survey Division
Understanding soil systems that characterize a region is critical to natural resource management. However, the knowledge gained through intensive study of local soil systems, which takes place annually as part of collegiate soil judging contests, is often poorly preserved for future use. In this study, field descriptions and laboratory data for 16 soil profiles described for the 2019 Region 5 Soil Judging Contest were used to characterize the soil system of the Central Nebraska Loess Hills and Central Loess Plains. Three landscape components of this soil system were analyzed: the loess uplands and rainwater basins, the transitional zone, and bottomlands. …
Drivers Of Pb, Sb And As Release From Spent Gunshot In Wetlands: Enhancement By Organic Matter And Native Microorganisms, Anna Potysz, Łukasz J. Binkowski, Jakub Kierczak, Barnett A. Rattner
Drivers Of Pb, Sb And As Release From Spent Gunshot In Wetlands: Enhancement By Organic Matter And Native Microorganisms, Anna Potysz, Łukasz J. Binkowski, Jakub Kierczak, Barnett A. Rattner
United States Geological Survey: Staff Publications
In many countries the use of lead-based ammunition is prevalent, and results in exposure and poisoning of waterfowl and other species of birds. In waterfowl hunting areas large quantities of spent shot may be deposited in wetland and terrestrial habitats. These pellets can undergo transformations, which are influenced by various abiotic and biotic factors. In addition to lead (Pb), other elements like antimony (Sb) and arsenic (As) can be leached from Pb shot into the environment. In vitro simulations that included organic matter and microorganisms were utilized to examine elemental leaching from gunshot. We found that leaching efficiency was the …
Limits To Coseismic Landslides Triggered By Cascadia Subduction Zone Earthquakes, Alex R.R. Grant, William T. Struble, Sean R. Lahusen
Limits To Coseismic Landslides Triggered By Cascadia Subduction Zone Earthquakes, Alex R.R. Grant, William T. Struble, Sean R. Lahusen
United States Geological Survey: Staff Publications
Landslides are a significant hazard and dominant feature throughout the landscape of the Pacific Northwest. However, the hazard and risk posed by coseismic landslides triggered by great Cascadia Subduction Zone (CSZ) earthquakes is highly uncertain due to a lack of local and global data. Despite a wealth of other geologic evidence for past earthquakes on the Cascadia Subduction Zone, no landslides have been definitively linked to such earthquakes, even in areas otherwise highly susceptible to failure. While shallow landslides may not leave a lasting topographical signature in the landscape, there are thousands of deep-seated landslides in Cascadia, and these deposits …
Neural Net Detection Of Seismic Features Related To Gas Hydrates And Free Gas Accumulations On The Northern U.S. Atlantic Margin, Urmi Majumdar, Nathaniel C. Miller, Carolyn D. Ruppel
Neural Net Detection Of Seismic Features Related To Gas Hydrates And Free Gas Accumulations On The Northern U.S. Atlantic Margin, Urmi Majumdar, Nathaniel C. Miller, Carolyn D. Ruppel
United States Geological Survey: Staff Publications
Bottom-simulating reflections (BSRs) that sometimes mark the base of the gas hydrate stability zone in marine sediments are often identified based on the reverse polarity reflections that cut across stratigraphic layering in seismic amplitude data. On the northern U.S. Atlantic margin (USAM) between Cape Hatteras and Hudson Canyon, legacy seismic data have revealed pronounced BSRs south of the deepwater extension of Hudson Canyon and more subtle ones from offshore Delaware south to Cape Hatteras, where the reflections sometimes follow stratigraphic layering. Using high-resolution seismic data acquired during the 2018 Mid-Atlantic Resource Imaging Experiment and a supervised neural net, we identify …
Establishment Of Invasive Black Carp (Mylopharyngodon Piceus) In The Mississippi River Basin: Identifying Sources And Year Classes Contributing To Recruitment, Gregory W. Whitledge, Patrick T. Kroboth, Duane C. Chapman, Quinton E. Phelps, Wes Sleeper, Jennifer Bailey, Jill A. Jenkins
Establishment Of Invasive Black Carp (Mylopharyngodon Piceus) In The Mississippi River Basin: Identifying Sources And Year Classes Contributing To Recruitment, Gregory W. Whitledge, Patrick T. Kroboth, Duane C. Chapman, Quinton E. Phelps, Wes Sleeper, Jennifer Bailey, Jill A. Jenkins
United States Geological Survey: Staff Publications
Black Carp (Mylopharyngodon piceus) was imported to the USA to control aquaculture pond snails. This species has escaped captivity and occurs in parts of the Mississippi River, several tributaries, and floodplain lakes, which is concerning due to potential competition with native fishes and predation on native mussels, many of which are imperiled. However, Black Carp captures have primarily been incidental by commercial fishers, and evidence of reproduction in the wild is limited. The objectives of this study were to assess relative abundance of aquaculture- origin and wild Black Carp using ploidy and otolith stable isotope analysis, identify spatial …
Very High Middle Miocene Surface Productivity On The U.S. Mid-Atlantic Shelf Amid Glacioeustatic Sea Level Variability, Marci M. Robinson, Harry J. Dowsett, Timothy D. Herbert
Very High Middle Miocene Surface Productivity On The U.S. Mid-Atlantic Shelf Amid Glacioeustatic Sea Level Variability, Marci M. Robinson, Harry J. Dowsett, Timothy D. Herbert
United States Geological Survey: Staff Publications
The Miocene Climatic Optimum (MCO) provides important insights into how the climate system operates under elevated temperatures and atmospheric CO2 levels. Few western North Atlantic paleotemperature or paleoecological records exist from the MCO, despite their importance for understanding both regional and global climate dynamics. Here we present quantitative MCO paleoecological data from the western North Atlantic, specifically from the Baltimore Gas & Electric (BG&E) marine sediment core from southern Maryland, USA. We examine alkenones and planktic foraminifera and document the first sea surface temperature (SST) and productivity estimates for the MCO and the Middle Miocene Climate Transition (MMCT) from …
Discovering Hidden Geothermal Signatures Using Non-Negative Matrix Factorization With Customized K-Means Clustering, V. V. Vesselinov, B. Ahmmed, M. K. Mudunuru, J. D. Pepin, E. R. Burns, D. L. Siler, S. Karra, R. S. Middleton
Discovering Hidden Geothermal Signatures Using Non-Negative Matrix Factorization With Customized K-Means Clustering, V. V. Vesselinov, B. Ahmmed, M. K. Mudunuru, J. D. Pepin, E. R. Burns, D. L. Siler, S. Karra, R. S. Middleton
United States Geological Survey: Staff Publications
Discovery of hidden geothermal resources is challenging. It requires the mining of large datasets with diverse data attributes representing subsurface hydrogeological and geothermal conditions. The commonly used play fairway analysis approach typically incorporates subject-matter expertise to analyze regional data to estimate geothermal characteristics and favorability. We demonstrate an alternative approach based on machine learning (ML) to process a geothermal dataset from southwest New Mexico (SWNM). The study region includes low- and medium-temperature hydrothermal systems. Several of these systems are not well characterized because of insufficient existing data and limited past explorative work. This study discovers hidden patterns and relations in …
Multi-Omics Responses In Tree Swallow (Tachycineta Bicolor) Nestlings From The Maumee Area Of Concern, Maumee River, Ohio, Chi Yen Tseng, Christine M. Custer, Thomas W. Custer, Paul M. Dummer, Natalie Karouna-Renier, Cole W. Matson
Multi-Omics Responses In Tree Swallow (Tachycineta Bicolor) Nestlings From The Maumee Area Of Concern, Maumee River, Ohio, Chi Yen Tseng, Christine M. Custer, Thomas W. Custer, Paul M. Dummer, Natalie Karouna-Renier, Cole W. Matson
United States Geological Survey: Staff Publications
A multi-omics approach was utilized to identify altered biological responses and functions, and to prioritize contaminants to assess the risks of chemical mixtures in the Maumee Area of Concern (AOC), Maumee River, OH, USA. The Maumee AOC is designated by the United States Environmental Protection Agency as having significant beneficial use impairments, including degradation of fish and wildlife populations, bird or animal deformities or reproduction problems, and loss of fish and wildlife habitat. Tree swallow (Tachycineta bicolor) nestlings were collected at five sites along the Maumee River, which included wastewater treatment plants (WWTPs) and industrial land-use sites. Polychlorinated …
Coastalimagelib: An Open- Source Python Package For Creating Common Coastal Image Products, Maile P. Mccann, Dylan L. Anderson, Christopher R. Sherwood, Brittany Bruder, A. Spicer Bak, Katherine L. Brodie
Coastalimagelib: An Open- Source Python Package For Creating Common Coastal Image Products, Maile P. Mccann, Dylan L. Anderson, Christopher R. Sherwood, Brittany Bruder, A. Spicer Bak, Katherine L. Brodie
United States Geological Survey: Staff Publications
CoastalImageLib is a Python library that produces common coastal image products intended for quantitative analysis of coastal environments. This library contains functions to georectify and merge multiple oblique camera views, produce statistical image products for a given set of images, and create subsampled pixel instruments for use in bathymetric inversion, surface current estimation, run-up calculations, and other quantitative analyses. This package intends to be an open-source broadly generalizable front end to future coastal imaging applications, ultimately expanding user accessibility to optical remote sensing of coastal environments. This package was developed and tested on data collected from the Argus Tower, a …
A Systematic Review And Meta-Analysis Of The Direct Effects Of Nutrients On Corals, Eileen M. Nalley, Lillian J. Tuttle, Emily E. Conklin, Alexandria L. Barkman, Devynn M. Wulstein, Madeline C. Schmidbauer, Megan J. Donahue
A Systematic Review And Meta-Analysis Of The Direct Effects Of Nutrients On Corals, Eileen M. Nalley, Lillian J. Tuttle, Emily E. Conklin, Alexandria L. Barkman, Devynn M. Wulstein, Madeline C. Schmidbauer, Megan J. Donahue
United States Geological Survey: Staff Publications
Chronic exposure of coral reefs to elevated nutrient conditions can modify the performance of the coral holobiont and shift the competitive interactions of reef organisms. Many studies have nowquantified the links between nutrients and coral performance, but fewhave translated these studies to directly address coastal water quality standards. To address this management need, we conducted a systematic review of peer-reviewed studies, public reports, and gray literature that examined the impacts of dissolved inorganic nitrogen (DIN: nitrate, nitrite, and ammonium) and dissolved inorganic phosphorus (DIP: phosphate) on scleractinian corals. The systematic review resulted in 47 studies with comparable data on coral …
Transcriptome Signatures Of Wastewater Effluent Exposure In Larval Zebrafish Vary With Seasonal Mixture Composition In An Effluent-Dominated Stream, Emma B. Meade, Luke R. Iwanowicz, Nicklaus Neureuther, Gregory H. Lefevre, Dana W. Kolpin, Hui Zhi, Shannon M. Meppelink, Rachael F. Lane, Angela Schmoldt, Aurash Mohaimani, Olaf Mueller, Rebecca D. Klaper
Transcriptome Signatures Of Wastewater Effluent Exposure In Larval Zebrafish Vary With Seasonal Mixture Composition In An Effluent-Dominated Stream, Emma B. Meade, Luke R. Iwanowicz, Nicklaus Neureuther, Gregory H. Lefevre, Dana W. Kolpin, Hui Zhi, Shannon M. Meppelink, Rachael F. Lane, Angela Schmoldt, Aurash Mohaimani, Olaf Mueller, Rebecca D. Klaper
United States Geological Survey: Staff Publications
Wastewater treatment plant (WWTP) effluent-dominated streams provide critical habitat for aquatic and terrestrial organisms but also continually expose them to complex mixtures of pharmaceuticals that can potentially impair growth, behavior, and reproduction. Currently, few biomarkers are available that relate to pharmaceutical-specific mechanisms of action. In the experiment reported in this paper, zebrafish (Danio rerio) embryos at two developmental stages were exposed to water samples from three sampling sites (0.1 km upstream of the outfall, at the effluent outfall, and 0.1 km below the outfall) during base-flow conditions from two months (January and May) of a temperate-region effluent-dominated stream …
Sinistral Shear During Middle Jurassic Emplacement Of The Matancilla Plutonic Complex In Northern Chile (25.4◦ S) As Evidence Of Oblique Plate Convergence During The Early Andean Orogeny, S.P. Mavor, J.S. Singleton, G. Heuser, R Gomila, N.M. Seymour, S. Williams, G. Arancibia
Sinistral Shear During Middle Jurassic Emplacement Of The Matancilla Plutonic Complex In Northern Chile (25.4◦ S) As Evidence Of Oblique Plate Convergence During The Early Andean Orogeny, S.P. Mavor, J.S. Singleton, G. Heuser, R Gomila, N.M. Seymour, S. Williams, G. Arancibia
United States Geological Survey: Staff Publications
component of oblique subduction into an intra-arc shear zone. We document a shear zone at latitude 25.4◦ S near Taltal, Chile that was associated with intrusion of the Matancilla Plutonic Complex at ~169 Ma to evaluate intra-arc deformation and possible tectonic plate configurations during this time period. Polyphase folding of Paleozoic metasedimentary rocks is overprinted by mylonitic fabrics that are most extensive in a zone up to 1.4 km wide in the thermal aureole of the granodioritic Matancilla pluton, where contact metamorphic andalusite porphyroblasts are synkinematic with fabric development. Mylonite in metasedimentary rocks is overprinted by a ~130 Ma …
Sinistral Shear During Middle Jurassic Emplacement Of The Matancilla Plutonic Complex In Northern Chile (25.4◦ S) As Evidence Of Oblique Plate Convergence During The Early Andean Orogeny, S. P. Mavor, J. S. Singleton, G. Heuser, R. Gomila, N. M. Seymour, S. Williams, G. Arancibia
Sinistral Shear During Middle Jurassic Emplacement Of The Matancilla Plutonic Complex In Northern Chile (25.4◦ S) As Evidence Of Oblique Plate Convergence During The Early Andean Orogeny, S. P. Mavor, J. S. Singleton, G. Heuser, R. Gomila, N. M. Seymour, S. Williams, G. Arancibia
United States Geological Survey: Staff Publications
Arc magmatism in a continental subduction zone facilitates rheological weakening of the rigid upper plate, and can accommodate the partitioned trench-parallel component of oblique subduction into an intra-arc shear zone. We document a shear zone at latitude 25.4◦ S near Taltal, Chile that was associated with intrusion of the Matancilla Plutonic Complex at ~169 Ma to evaluate intra-arc deformation and possible tectonic plate configurations during this time period. Polyphase folding of Paleozoic metasedimentary rocks is overprinted by mylonitic fabrics that are most extensive in a zone up to 1.4 km wide in the thermal aureole of the granodioritic Matancilla …
Discovering Hidden Geothermal Signatures Using Non-Negative Matrix Factorization With Customized K-Means Clustering, V.V. Vesselinov, B. Ahmmed, M.K. Mudunuru, J.D. Pepin, E.R. Burns, D.L. Siler, S. Karra, R.S. Middleton
Discovering Hidden Geothermal Signatures Using Non-Negative Matrix Factorization With Customized K-Means Clustering, V.V. Vesselinov, B. Ahmmed, M.K. Mudunuru, J.D. Pepin, E.R. Burns, D.L. Siler, S. Karra, R.S. Middleton
United States Geological Survey: Staff Publications
Discovery of hidden geothermal resources is challenging. It requires the mining of large datasets with diverse data attributes representing subsurface hydrogeological and geothermal conditions. The commonly used play fairway analysis approach typically incorporates subject-matter expertise to analyze regional data to estimate geothermal characteristics and favorability. We demonstrate an alternative approach based on machine learning (ML) to process a geothermal dataset from southwest New Mexico (SWNM). The study region includes low- and medium-temperature hydrothermal systems. Several of these systems are not well characterized because of insufficient existing data and limited past explorative work. This study discovers hidden patterns and relations in …
The Effects Of Estradiol-17Β On The Sex Reversal, Survival, And Growth Of Green Sunfish Lepomis Cyanellus, Chad N. Teal, Daniel J. Schill, Susan B. Fogelson, Colby M. Roberts, Kevin Fitzsimmons, Javan M. Bauder, William T. Stewart, Scott A. Bonar
The Effects Of Estradiol-17Β On The Sex Reversal, Survival, And Growth Of Green Sunfish Lepomis Cyanellus, Chad N. Teal, Daniel J. Schill, Susan B. Fogelson, Colby M. Roberts, Kevin Fitzsimmons, Javan M. Bauder, William T. Stewart, Scott A. Bonar
United States Geological Survey: Staff Publications
The feminization of green sunfish Lepomis cyanellus could expand their utility as a game fish or aquacultured species by preventing overcrowding and precocious reproduction in stocked systems. Feminization of green sunfish could also help elucidate information on their sex determination system. We report the feminization of green sunfish cohorts via oral administration of estradiol-17β (E2) during early development. A low-dose (100 E2 mg per kg of diet) and a high-dose (150 E2 mg per kg of diet) experimental E2 treatment were fed to juvenile green sunfish from 30 to 90 days post-hatch. Fish were subsequently evaluated for any treatment effect …
Climate Change Alters Aging Patterns Of Reservoir Aquatic Habitats, Leandro E. Miranda, Nicky M. Faucheux
Climate Change Alters Aging Patterns Of Reservoir Aquatic Habitats, Leandro E. Miranda, Nicky M. Faucheux
United States Geological Survey: Staff Publications
Two slow-moving developments are threatening reservoir aquatic habitats globally: aging and climate change. These events are projected to transform reservoir aquatic habitats in various and often unpredictable ways. Aging affects in-lake habitats directly, whereas climate change affects both in-lake and off-lake conditions. Climate change is expected to accelerate and, in some instances, possibly decelerate aging. Aging can be indexed as functional age, an index that signals the position of a reservoir along its lifespan relying on inlake descriptors of aquatic habitat. Using existing habitat datasets and climate projections, we developed semi-quantitative predictions about the effect of climate change on reservoir …
Sediment Source Fingerprinting As An Aid To Large-Scale Landscape Conservation And Restoration: A Review For The Mississippi River Basin, Zhen Xu, Patrick Belmont, Janice Brahney, Allen C. Gellis
Sediment Source Fingerprinting As An Aid To Large-Scale Landscape Conservation And Restoration: A Review For The Mississippi River Basin, Zhen Xu, Patrick Belmont, Janice Brahney, Allen C. Gellis
United States Geological Survey: Staff Publications
Reliable quantitative information on sediment sources to rivers is critical to mitigate contamination and target conservation and restoration actions. However, for large-scale river basins, determination of the relative importance of sediment sources is complicated by spatiotemporal variability in erosional processes and sediment sources, heterogeneity in sediment transport and deposition, and a paucity of sediment monitoring data. Sediment source fingerprinting is an increasingly adopted field-based technique that identifies the nature and relative source contribution of sediment transported in waterways. Notably, sediment source fingerprinting provides information that is independent of other field, modeling, or remotely sensed techniques. However, the diversity in sampling, …
Seasonality Of Precipitation In The Southwestern United States During The Late Pleistocene Inferred From Stable Isotopes In Herbivore Tooth Enamel, Matthew J. Kohn, Kathleen B. Springer, Jeffrey S. Pigati, Linda M. Reynard, Amanda E. Drewicz, Justin Crevier, Eric Scott
Seasonality Of Precipitation In The Southwestern United States During The Late Pleistocene Inferred From Stable Isotopes In Herbivore Tooth Enamel, Matthew J. Kohn, Kathleen B. Springer, Jeffrey S. Pigati, Linda M. Reynard, Amanda E. Drewicz, Justin Crevier, Eric Scott
United States Geological Survey: Staff Publications
The late Pleistocene was a climatically dynamic period, with abrupt shifts between cool-wet and warmdry conditions. Increased effective precipitation supported large pluvial lakes and long-lived spring ecosystems in valleys and basins throughout the western and southwestern U.S., but the source and seasonality of the increased precipitation are debated. Increases in the proportions of C4/(C4+ C3) grasses in the diets of large grazers have been ascribed both to increases in summer precipitation and lower atmospheric CO2 levels. Here we present stable carbon and oxygen isotope data from tooth enamel of late Pleistocene herbivores recovered …
Collateral Damage: Anticoagulant Rodenticides Pose Threats To California Condors, Garth Herring, Collin A. Eagles-Smith, Rachel Wolstenholme, Alacia Welch, Chris West, Barnett A. Rattner
Collateral Damage: Anticoagulant Rodenticides Pose Threats To California Condors, Garth Herring, Collin A. Eagles-Smith, Rachel Wolstenholme, Alacia Welch, Chris West, Barnett A. Rattner
United States Geological Survey: Staff Publications
Anticoagulant rodenticides (ARs) are widespread environmental contaminants that pose risks to scavenging birds because they routinely occur within their prey and can cause secondary poisoning. However, little is known about AR exposure in one of the rarest avian scavengers in the world, the California condor (Gymnogyps californianus). We assessed AR exposure in California condors and surrogate turkey vultures (Cathartes aura) to gauge potential hazard to a proposed future condor flock by determining how application rate and environmental factors influence exposure. Additionally, we examined whether ARs might be correlated with prolonged blood clotting time and potential mortality …
Limited Rigor In Studies Of Raptor Mortality And Mitigation At Wind Power Facilities, Tara J. Conkling, Christopher J.W. Mcclure, Sandra Cuadros, Scott R. Loss, Todd E. Katzner
Limited Rigor In Studies Of Raptor Mortality And Mitigation At Wind Power Facilities, Tara J. Conkling, Christopher J.W. Mcclure, Sandra Cuadros, Scott R. Loss, Todd E. Katzner
United States Geological Survey: Staff Publications
Wind power is an expanding source of renewable energy. However, there are ecological challenges related to wind energy generation, including collisions of wildlife with turbines. Lack of rigor, and variation in study design, together limit efforts to understand the broad-scale effects of wind power infrastructure on wildlife populations. It is not clear, however, whether these types of limitations apply to groups of birds such as raptors that are particularly vulnerable to negative effects of wind energy. We reviewed 672 peer-reviewed publications, unpublished reports, and citations from 321 wind facilities in 12 countries to evaluate methods used to monitor and mitigate …
The Diatom Dark Ages: Identification Of Mid-Cretaceous Arctic Platform Diatoms From The Basal Transgression Of The Kanguk Formation, Devon Island, Nunavut, Canada, Megan Heins
Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research
The lower part of the mid-Cretaceous Kanguk Formation (Lower Turonian interval) contains an important paleontological record crucial to the characterization of a poorly known interval of fossil marine diatoms history. Kanguk Formation mudstones are exposed in a ~200 m-thick section on Devon Island, Nunavut, Canadian High Arctic. Diatoms at this location are well-preserved due to shallow burial on this Arctic Platform site. The rock sequence was protected from glacial erosion that removed much of the Cretaceous record by being down-faulted in a linear graben. Study of these well-preserved fossil diatoms allows for a documentation of the assemblage, identification of potentially …