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Page 257, results 6401 - 6425

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Earthquake magnitude and Lg Q variations between the Grenville and northern Appalachian geologic provinces of eastern Canada
H.K. Claire Perry, Allison L. Bent, Daniel E. McNamara, Stephen Crane, Michal Kolaj
2020, Bulletin of the Seismological Society of America (110) 698-714
This article assesses the ability of regionally specific, frequency‐dependent crustal attenuation (⁠1/Q">1/Q⁠) to reduce mean magnitude discrepancies between seismic stations in the northern Appalachian and Grenville provinces (NAP and GP)...
The response of stream ecosystems in the Adirondack region of New York to historical and future changes in atmospheric deposition of sulfur and nitrogen
Shuai Shao, Charles T. Driscoll, Timothy J. Sullivan, Douglas A. Burns, Barry P. Baldigo, Gregory B. Lawrence, Todd C. McDonnell
2020, Science of the Total Environment (716)
The present-day acid-base chemistry of surface waters can be directly linked to contemporary observations of acid deposition; however, pre-industrial conditions are key to predicting the potential future recovery of stream ecosystems under decreasing loads of atmospheric sulfur (S) and nitrogen (N) deposition. The integrated biogeochemical model PnET-BGC was applied to...
Mapping habitat suitability at range-wide scales: Spatially explicit distribution models to inform conservation and research for marsh birds
Bryan S. Stevens, Courtney J. Conway
2020, Conservation Science and Practice (2)
Habitat Loss is a primary cause of species decline, and predicting the distribution of quality habitats across broad scales is needed for conservation of rare species. Secretive marsh birds are a group of emergent-wetland specialists that include multiple threatened and endangered species whose populations have been impacted by wetland loss...
The Modern Geological Survey; a model for research, innovation, synthjesis: A USGS perspective
Suzette Kimball, Martin B. Goldhaber, Jill S. Baron, Victor F. Labson
2020, Book chapter, Folding and fracturing of rocks: 50 years of research since the seminal text book of J. G. Ramsay
Geological Surveys have long filled the role of providing Earth system science data and knowledge. These functions are increasingly complicated by accelerating environmental and societal change. Here we describe the USGS response to these evolving conditions. Underpinning the USGS approach is the recognition that many of the issues...
Dynamic Habitat Disturbance and Ecological Resilience (DyHDER): Modeling population responses to habitat condition
Brendan P. Murphy, Timothy E. Walsworth, Patrick Belmont, Mary M. Conner, Phaedra E. Budy
2020, Ecosphere (11)
Understanding how populations respond to spatially heterogeneous habitat disturbance is as critical to conservation as it is challenging. Here, we present a new, free, and open-source metapopulation model: Dynamic Habitat Disturbance and Ecological Resilience (DyHDER), which incorporates subpopulation habitat condition and connectivity into a population viability analysis framework. Modeling temporally...
Influence of grain size and shape on volcanic ash electrical conductivity
Taylor Woods, Kimberly Genareau, Kristi L. Wallace
2020, Journal of Volcanology and Geothermal Research (393)
Few studies have examined the electrical properties of volcanic ash or considered the effects of physical characteristics, such as grain size and shape on its electrification. This study measures the resistivity of eight volcanic ash samples, three milled-samples and five natural ashfall samples from Alaska, U.S.A., using a current amplifier and examines the...
Simulation of water-management scenarios for the Mississippi Delta
Connor J. Haugh, Courtney D. Killian, Jeannie R. B. Barlow
2020, Scientific Investigations Report 2019-5116
To compare the effectiveness of proposed alternative water-supply scenarios on future water availability in the Mississippi Delta, the U.S. Geological Survey and the Mississippi Department of Environmental Quality are collaborating on the update and enhancement of an existing regional groundwater-flow model of the area. Through this collaboration, the model has...
Persistence and plasticity in conifer water-use strategies
Max Berkelhammer, Chris Still, Francois Ritter, Matthew Winnik, Lesleigh Anderson, Rosemary Carroll, Mariah Carbone, Kenneth Williams
2020, Journal of Geophysical Research: Biogeosciences (125)
The selective use of seasonal precipitation by vegetation is critical to understanding the residence time and flow path of water in watersheds, yet there are limited datasets to test how climate alters these dynamics. Here, we use measurements of the seasonal cycle of tree ring 18O for two widespread conifer...
Evolution of the submarine–subaerial edifice of Bogoslof volcano, Alaska, during its 2016–2017 eruption based on analysis of satellite imagery
Christopher F. Waythomas, Kim M. Angeli, Rick Wessels
2020, Bulletin of Volcanology (82)
The 2016–2017 eruption of Bogoslof volcano involved at least 70 detected eruptive events between mid-December 2016 and August 30, 2017. Acquisition of high-resolution satellite imagery throughout the duration of the eruptive period allowed us to document and map the various morphologic changes that occurred on the...
Development of a global seismic risk model
Vitor Silva, Desmond Amo-Oduro, Alejandro Calderon, Catarina Costa, Jamal Dabbeek, Venetia Despotaki, Luis Martins, Marco Pagani, Anirudh Rao, Michele Simionato, Daniele Vigano, Catalina Yepes-Estrada, Ana Beatriz Acevedo, Helen Crowley, Nick Horspool, Kishor S. Jaiswal, Murray Journeay, Massimiliano Pittore
2020, Earthquake Spectra (36) 372-394
Since 2015 the Global Earthquake Model (GEM) Foundation and its partners have been supporting regional programmes and bilateral collaborations to develop an open global earthquake risk model. These efforts led to the development of a repository of probabilistic seismic hazard models, a global exposure dataset comprising structural and occupancy information...
High-resolution mapping of the freshwater-brine interface using deterministic and Bayesian inversion of airborne electromagnetic data at Paradox Valley, USA
Lyndsay B. Ball, Paul A. Bedrosian, Burke J. Minsley
2020, Hydrogeology Journal (28) 941-954
Salt loads in the Colorado River Basin are a primary water quality concern. Natural groundwater brine discharge to the Dolores River where it passes through the collapsed salt anticline of the Paradox Valley in western Colorado is a significant source of salt to the Colorado River. An airborne...
Influence of population density and length structure on angler catch rate in kokanee fisheries
Zachary B. Klein, Michael C. Quist, Daniel J. Schill, Andrew M. Dux, Matthew P. Corsi
2020, North American Journal of Fisheries Management (40) 182-189
Management agencies are often charged with providing fisheries that lead to angler participation. Catch rate is one of the primary drivers of angler participation but can be influenced by a suite of factors, including population structure (e.g., density and size structure). The complexity of understanding how population structure influences angler...
Pacific Continental Shelf Environmental Assessment (PaCSEA): Characterization of Seasonal Water Masses within the Northern California Current System Using Airborne Remote Sensing off Northern California, Oregon, and Washington, 2011–2012
J A Schulien, Josh Adams, Jonathan J. Felis
2020, Report
Here, we use ocean color measurements (Figure 1) and sea surface temperature (SST) data collected using sensors mounted on low-flying aircraft to characterize NCCS water masses and identify patterns among seasons and between years. To accomplish this, we applied k-means clustering to measured and derived ecologically-relevant physical and bio-optical variables...
Influence of remediation on sediment toxicity within the Grand Calumet River, Indiana, USA
Jeffery A. Steevens, John M. Besser, Rebecca A. Dorman, Daniel W. Sparks
2020, Chemosphere (249)
The Grand Calumet River (GCR), located in northern Indiana, is contaminated due to a wide range of historical industrial activities. This study was conducted to determine the influence of sediment remediation within the GCR on concentrations of chemical contaminants and toxicity to sediment-dwelling organisms. Between 2005 and 2016, sediments with...
Direct trace element determination in oil and gas produced waters with inductively coupled plasma - Optical emission spectrometry (ICP-OES): Advantages of high salinity tolerance
Aaron M. Jubb, Mark Engle, Jessica Chenault, Madalyn Blondes, Cloelle G. Danforth, Colin Doolan, Tanya Gallegos, Dan Mueller, Jenna Shelton
2020, Geostandards and Geoanalytical Research (44) 385-397
Waters co-produced during petroleum extraction are the largest waste stream from oil and gas development. Reuse or disposal of these waters is difficult due to their high salinities and the sheer volumes generated. Produced waters may also contain valuable mineral commodities. While an understanding of produced water trace element composition...
Predictive relations between acid-base chemistry and fish assemblages in streams of the Adirondack Mountains
Diane Bertok, Barry P. Baldigo, Scott D. George
2020, NYSERDA Report 20-04
Surface waters across much of New York State’s Adirondack Mountains were acidified in the late 20th century but began to recover following the 1990 Title IV Amendments to the Clean Air Act. Previous assessments of acidification recovery in the Adirondacks have generally been based on surface water chemistry data and...
Expert bioblitzes facilitate non-native fish tracking and interagency partnerships
Pamela J. Schofield
2020, Management of Biological Invasions (11) 139-154
Documenting the distribution and composition of non-native species populations can be challenging, especially when species cross jurisdictional boundaries that require interagency coordination. Herein I report the development of three tools that have been used in Florida over the past seven years to assist with tracking of non-native fishes: 1) an...
Applications of correlative light and electron microscopy (CLEM) to organic matter in the North American shale petroleum systems
Brett J. Valentine, Paul C. Hackley
2020, Book chapter, Mudstone diagenesis: Research perspectives for shale hydrocarbon reservoirs, seals, and source rocks
Scanning electron microscopy (SEM) has revolutionized our understanding of shale petroleum systems through microstructural characterization of dispersed organic matter (OM). However, due to the low atomic weight of carbon, all OM appears black in SEM (BSE image) regardless of differences in thermal maturity or OM type (kerogen types or solid...
Habitat affinities and at-sea ranging behaviors among main Hawaiian Island seabirds: Breeding seabird telemetry, 2013–2016
Josh Adams, Jonathan J. Felis, Max Czapanskiy
2020, Report
Recent Hawaiʻi state clean energy policy mandates and federal interest in developing offshore renewable energy resources have prompted unsolicited lease requests for offshore wind energy infrastructure (OWEI) to be located in ocean waters off Hawaiʻi. This study describing at-sea ranging behaviors for five seabirds was intended to provide new information...
Estimating late 19th century hydrology in the Greater Everglades Ecosystem: An integration of paleoecologic data and models
Frank E. Marshall, Christopher E. Bernhardt, G. Lynn Wingard
2020, Frontiers in Environmental Science (8)
Determining hydrologic conditions prior to instrumental records is a challenge for restoration of freshwater ecosystems worldwide. Paleoecologic data provide this information on past conditions and when these data are used to adjust hydrologic models, allow conditions to be hindcast that may not be directly estimated from the paleo-data alone....
A system design for implementing advanced feature descriptions for a map knowledge base
Matthew Wagner, Dalia E. Varanka, E. Lynn Usery
2020, Scientific Investigations Report 2019-5148
A prototype system to explore Linked Data that semantically integrates geospatial data in various formats from different publication sources with data from The National Map of the U.S. Geological Survey is presented. The focus is on accessing advanced feature descriptions for data from The National Map with data coreferenced from...
A geospatially resolved wetland vulnerability index: Synthesis of physical drivers
Zafer Defne, Alfredo Aretxabaleta, Neil K. Ganju, Tarandeep S. Kalra, Daniel K. Jones, Kathryn E.L. Smith
2020, PLoS ONE (15)
Assessing wetland vulnerability to chronic and episodic physical drivers is fundamental for establishing restoration priorities. We synthesized multiple data sets from E.B Forsythe National Wildlife Refuge, New Jersey, to establish a wetland vulnerability metric that integrates a range of physical processes, regulatory information and physical/biophysical features. The geospatial data are based on aerial imagery,...
Numerical simulation of groundwater availability in central Moloka‘i, Hawai‘i
Delwyn S. Oki, John A. Engott, Kolja Rotzoll
2020, Scientific Investigations Report 2019-5150
Since the 1990s, increased chloride concentrations of water pumped from wells (much of which is used for drinking water) and the effects of withdrawals on groundwater-dependent ecosystems have led to concerns over groundwater availability on the island of Molokaʻi, Hawaiʻi. An improved understanding of the hydrologic effects of proposed groundwater...
Climate relationships with increasing wildfire in the southwestern US from 1984 to 2015
Stephanie Mueller, Andrea E. Thode, Ellis Q. Margolis, Larissa Yocom, Jesse M. Young, Jose M. Iniguez
2020, Forest Ecology and Management (460)
Over the last several decades in forest and woodland ecosystems of the southwestern United States, wildfire size and severity have increased, thereby increasing the vulnerability of these systems to type conversions, invasive species, and other disturbances. A combination of land use history and climate change is widely thought to be...
Upper plate heterogeneity along the Southern Hikurangi Margin, New Zealand
Stuart Henrys, Donna Eberhart-Phillips, Dan Bassett, Rupert Sutherland, David Okaya, Martha Savage, Dominic Evanzia, Tim A. Stern, Hiroshi Sato, Kimihiro Mochizuki, Takaya Iwasaki, Eiji Kurashimo, Anya Seward, Aaron Wech
2020, Geophysical Research Letters (47)
Controlled and natural source seismic data are used to build a 3-D P wave model for southern North Island, New Zealand, where the Pacific Plate subducts beneath the Australian Plate at a rate of ~41 mm/year. Our analysis reveals an abrupt along-strike transition in overthrusting plate structure within Cook...