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Page 501, results 12501 - 12525

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Revisiting California’s past great earthquakes and long-term earthquake rate
Susan E. Hough, Morgan T. Page, Leah Salditch, Molly M. Gallahue, Madeleine C. Lucas, James S. Neely, Seth Stein
2021, Bulletin of the Seismological Society of America (111) 356-370
In this study, we revisit the three largest historical earthquakes in California—the 1857 Fort Tejon, 1872 Owens Valley, and 1906 San Francisco earthquakes—to review their published moment magnitudes, and compare their estimated shaking distributions with predictions using modern ground‐motion models (GMMs) and ground‐motion intensity conversion equations. Currently accepted moment magnitude...
Modeling areal measures of campsite impacts on the Appalachian National Scenic Trail to enhance ecological sustainability
Johanna R. Arredondo, Jeffrey L. Marion, Fletcher P. Meadema, Jeremy F. Wimpey
2021, Journal of Environmental Management (279)
Campsite impacts in protected natural areas are most effectively minimized by a containment strategy that focuses use on a limited number of sustainable campsites that spatially concentrate camping activities. This research employs spatial autoregressive (SAR) modeling to evaluate the relative influence...
Limited mantle hydration by bending faults at the Middle America Trench
Nathaniel C. Miller, Danile Lizarralde, John A. Collins, Steven Holbrook, Harm van Avendonk
2021, Journal of Geophysical Research (25)
Seismic anisotropy measurements show that upper mantle hydration at the Middle America Trench (MAT) is limited to serpentinization and/or water in fault zones, rather than distributed uniformly. Subduction of hydrated oceanic lithosphere recycles water back into the deep mantle, drives arc volcanism, and affects seismicity at...
Performance of the ecosystem demography model (EDv2.2) in simulating gross primary production capacity and activity in a dryland study area
Hamid Dashti, Karun Pandit, Nancy F. Glenn, Douglas J. Shinneman, Gerald N. Flerchinger, Andrew A. Hudak, Marie Anne de Graaf, Alejandro N Flores, Susan L. Ustin, Nayani Ilangakoon, Aaron W. Fellows
2021, Agricultural and Forest Meteorology (297)
Dryland ecosystems play an important role in the global carbon cycle, including regulating the inter-annual global carbon sink. Dynamic global vegetation models (DGVMs) are essential tools that can help us better understand carbon cycling in different ecosystems. Currently, there is limited knowledge of the performance of these models in drylands...
Heed the data gap: Guidelines for using incomplete datasets in annual stream temperature analyses
Zachary C. Johnson, Brittany G. Johnson, Martin A. Briggs, Craig D. Snyder, Nathaniel P. Hitt, Warren Devine
2021, Ecological Indicators (122)
Stream temperature data are useful for deciphering watershed processes important for aquatic ecosystems. Accurately extracting signal trends from stream temperature is essential for predicting responses of environmental and ecological indicators to change. Missing data periods are common for various reasons, and...
High elevation ice patch documents Holocene climate variability in the northern Rocky Mountains
Nathan J. Chellman, Gregory T. Pederson, Craig Lee, Dave McWethy, Kathryn Pusman, Jeffery R. Stone, Sabrina R. Brown, Joseph R. McConnell
2021, Quaternary Science Advances (3)
Paleoclimate records from ice cores generally are considered to be the most direct indicators of environmental change, but are rare from mid-latitude, continental regions such as the western United States. High-elevation ice patches are known to be important archaeological archives in alpine regions and potentially could provide records important for...
Novel diagnostic tests for the putative agent of bacterial gill disease in Pacific razor clams (Siliqua patula)
Brooke A Travis, William N. Batts, Maya Groner, Paul Hershberger, Steven C. Fradkin, Carla M. Conway, Linda Park, Maureen K. Purcell
2021, Journal of Invertebrate Pathology (178)
Nuclear inclusion X (NIX) is a gamma proteobacteria that infects the nuclei of gill epithelial cells in Pacific razor clams. NIX has been associated with clam die-offs in coastal Washington. A quantitative PCR (qPCR) assay was developed to detect NIX in Pacific razor clams, and assay specificity was confirmed by chromogenic in...
Spatial patterns and drivers of nonperennial flow regimes in the contiguous United States
John C. Hammond, Margaret Zimmer, Margaret Shanafield, Kendra E. Kaiser, Sarah E Godsey, Meryl C. Mims, Samuel Zipper, Ryan Burrow, Stephanie K. Kampf, Walter Dodds, C. Nathan Jones, Corey Krabbenhoft, Kate Boersma, Thibault Datry, Julian D. Olden, George H. Allen, Adam N. Price, Katie H. Costigan, Rebecca Hale, Adam S Ward, Daniel Allen
2021, Geophysical Research Letters (48)
Over half of global rivers and streams lack perennial flow, and understanding the distribution and drivers of their flow regimes is critical for understanding their hydrologic, biogeochemical, and ecological functions. We analyzed nonperennial flow regimes using 540 U.S. Geological Survey watersheds across the contiguous United States from 1979 to 2018....
The 2018 update of the US National Seismic Hazard Model: Additional period and site class data
Allison Shumway, Mark D. Petersen, Peter M. Powers, Sanaz Rezaeian, Kenneth S. Rukstales, Brandon Clayton
2021, Earthquake Spectra (37) 1145-1161
As part of the update of the 2018 National Seismic Hazard Model (NSHM) for the conterminous United States (CONUS), new ground motion and site effect models for the central and eastern United States were incorporated, as well as basin depths from local seismic velocity models in four western US (WUS)...
Pesticides and pesticide degradates in groundwater used for public supply across the United States: Occurrence and human-health context
Laura M. Bexfield, Kenneth Belitz, Bruce D. Lindsey, Patricia Toccalino, Lisa H. Nowell
2021, Environmental Science & Technology (55) 362-372
This is the first assessment of groundwater from public-supply wells across the United States to analyze for >100 pesticide degradates and to provide human-health context for degradates without benchmarks. Samples from 1204 wells in aquifers representing 70% of the volume pumped for drinking supply were analyzed for 109 pesticides (active...
Determination of four arsenic species in environmental water samples by liquid chromatography- inductively coupled plasma - tandem mass spectrometry
Sarah Stetson, Caitlyn Margaret Lawrence, Susan Melissa Whitcomb, Christopher J. Kanagy
2021, MethodsX (8)
Robust and sensitive methods for monitoring inorganic and organic As species As(III), As(V), dimethylarsinate (DMA), and monomethylarsonate (MMA) in environmental water are necessary to understand the toxicity and redox processes of As in a specific environment. The method is sufficiently sensitive and selective to ensure accurate and precise quantitation of...
Direct observation of the depth of active groundwater circulation in an alpine watershed
Andrew H. Manning, Lyndsay B. Ball, Richard Wanty, Kenneth H. Williams
2021, Water Resources Research (57)
The depth of active groundwater circulation is a fundamental control on stream flows and chemistry in mountain watersheds, yet it remains challenging to characterize and is rarely well constrained. We collected hydraulic conductivity, hydraulic head, temperature, chemical, noble gas, and 3H/3He groundwater age data from discrete levels in two boreholes 46...
The Alaska convergent margin backstop splay fault zone, a potential large tsunami generator between the frontal prism and continental framework
Roland von Huene, John J. Miller, Anne Krabbenhoeft
2021, Geochemistry, Geophysics, and Geosystems (22)
The giant tsunami that swept the Pacific from Alaska to Antarctica in 1946 was generated along one of three Alaska Trench instrumentally recorded aftershock areas following great and giant earthquakes. Aftershock areas were investigated during the past decade with multibeam bathymetry, ocean bottom seismograph wide‐angle seismic, reprocessed legacy, and new...
Pervasive low-velocity layer atop the 410-km discontinuity beneath the northwest Pacific subduction zone: Implications for rheology and geodynamics
Guangjie Han, Juan Li, Guangrui Guo, Walter D. Mooney, Shun-Ichiro Karato, David A. Yuen
2021, Earth and Planetary Science Letters (554)
Regional triplication waveforms of five intermediate-depth events are modeled to simultaneously obtain the compressional (P) and shear (SH) wave velocity structure beneath northwestern Pacific subduction zone. Both the P- and SH-wave velocity models for three different sub-regions show a low-velocity layer (LVL) with a thickness of ∼55-80 km lying above the...
Permafrost promotes shallow groundwater flow and warmer headwater streams
Ylva Sjoberg, Adam K. Janke, S Painter, E. Coonradt, Michael P. Carey, Jonathan A. O’Donnell, Joshua C. Koch
2021, Water Resources Research (57)
The presence of permafrost influences the flow paths of water through Arctic landscapes and thereby has the potential to impact stream discharge and thermal regimes. Observations from eleven headwater streams in Alaska showed that July water temperatures were higher in catchments with more near‐surface permafrost. We apply a fully coupled...
Machine learning predictions of pH in the Glacial Aquifer System, Northern USA
Paul E. Stackelberg, Kenneth Belitz, Craig J. Brown, Melinda L. Erickson, Sarah M. Elliott, Leon J. Kauffman, Katherine Marie Ransom, James E. Reddy
2021, Groundwater (37) 531-543
A boosted regression tree model was developed to predict pH conditions in three dimensions throughout the glacial aquifer system of the contiguous United States using pH measurements in samples from 18,386 wells and predictor variables that represent aspects of the hydrogeologic setting. Model results indicate that the carbonate content of...
Characterizing strain between rigid crustal blocks in the southern Cascadia forearc: Quaternary faults and folds of the northern Sacramento Valley, California
Stephen J. Angster, Steven G. Wesnousky, Paula Figueiredo, Lewis A. Owen, Thomas Sawyer
2021, Geology (49) 387-391
Topographic profiles across late Quaternary surfaces in the northern Sacramento Valley (California, USA) show offset and progressive folding on series of active east- and northeast—trending faults and folds. Optically stimulated luminescence ages on deposits draping a warped late Pleistocene river terrace yielded differential incision rates along the Sacramento River and...
The impact of ventilation patterns on calcite dissolution rates within karst conduits
Matthew D. Covington, Katherine J. Knierim, Holly H Young, Josue Rodriguez, Hannah Gnoza
2021, Journal of Hydrology (593)
Erosion rates in streams vary dramatically over time, as differences in streamflow and sediment load enhance or inhibit erosion processes. Within cave streams, and other bedrock channels incising soluble rocks, changes in water chemistry are an important factor in determining how erosion rates will vary in both time and space....
Effect of temperature, nitrate concentration, pH and bicarbonate addition on biomass and lipid accumulation in the sporulating green alga PW95
Luisa Corredor, Elliott Barnhart, Albert E. Parker, Robin Gerlach, Matthew W. Fields
2021, Algal Research (53)
The mixed effects of temperature (20 °C, 25 °C and 30 °C), nitrate concentration (0.5 mM and 2.0 mM), pH buffer, and bicarbonate addition (trigger) on biomass growth and lipid accumulation were investigated in the environmental alga PW95 during batch experiments in standardized growth medium. PW95...
Periodic dike intrusions at Kīlauea Volcano, Hawaii
Emily K. Montgomery-Brown, Asta Mikijus
2021, Geology (49) 397-401
Forecasting heightened magmatic activity is key to assessing and mitigating global volcanic hazards, including eruptions from lateral rift zones at basaltic volcanoes. At Kı-lauea volcano, Hawai’i (United States), planar dikes intrude its east rift zone (ERZ) and repeatedly affect the same segments. Here we show...
Resource partitioning across a trophic gradient between a freshwater fish and an intraguild exotic
Richard Kraus, Joseph Schmitt, Kevin R. Keretz
2021, Ecology of Freshwater Fish (30) 320-333
The introduction of exotic species has the potential to cause resource competition with native species and may lead to competitive exclusion when resources are limiting. On the other hand, information is lacking to predict under what alternate trophic conditions coexistence may occur. Comparing diets of native yellow perch Perca flavescens and nonindigenous...
Examining the potential conflict between sea otter recovery and Dungeness crab fisheries in California
Andre M. Boustany, David Hernandez, Emily A Miller, Fujii. Jessica, Teri E. Nicholson, Joseph A. Tomoleoni, Kyle S. Van Houtan
2021, Biological Conservation (253)
Human exploitation of marine mammals led to precipitous declines in many wild populations within the last three centuries. Legal protections enacted throughout the 20th century have enabled the recovery of many of these species and some recoveries have resulted in conflict...