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ShakeMap is a product of the USGS Earthquake Hazards Program in conjunction with the regional seismic networks. ShakeMaps provide near-real-time maps of ground motion and shaking intensity following significant earthquakes. These maps are used by federal, state, and local organizations, both public and private, for post-earthquake response and recovery, public and scientific information, as well as for preparedness exercises and disaster planning.
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The NEIC global earthquake bulletin is called the Preliminary Determination of Epicenters or PDE, and is one of many discrete products in the ANSS Comprehensive Catalog (ComCat). We use the word "Preliminary" for our final bulletin because the Bulletin of the International Seismological Centre is considered to be the final global archive of parametric earthquake data, in other words phase arrival (“pick”) times and amplitudes.
Freshwater mussels (Unionidae) are among the most imperiled groups of organisms in the world. Unionids are plagued with a lack of basic information regarding species distributions, life history characteristics, and ecological and biological requirements. We assessed the influence of hydrologic factors on the occurrence of the Suwannee Moccasinshell, Medionidus walkeri, a federally threatened freshwater mussel species endemic to the Suwannee River basin in Georgia and Florida. We also assessed the influence of survey effort on detection of M. walkeri during field surveys. All current (2013-2016) mussel survey records in the Suwannee River Basin were compiled, and cumulative discharge contributed by upstream springs...
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The accretion history of fringing salt marshes located on the south shore of Cape Cod is reconstructed from sediment cores collected in low and high marsh vegetation zones. These marshes are micro-tidal, with a mean tidal range of 0.442 m. Their location within protected embayments and the absence of large rivers results in minimal sediment supply and a dominance of organic matter contributions to sediment peat. Age models based on 210-lead and 137-cesium are constructed to evaluate how vertical accretion and carbon burial rates have changed over the past century. The continuous rate of supply age model was used to age date 11 cores (10 low marsh and 1 high marsh) across four salt marshes. Both vertical accretion...
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This dataset contains reflectance and transmission spectra of unexpanded and expanded vermiculite ore, and handpicked flakes of phlogopite, hydrobiotite, and vermiculite. These samples were collected from mines near Enoree, South Carolina; Libby, Montana; Louisa, Virginia; Palabora, Llano, Texas; and South Africa. Spectra are identified as either reflectance or transmission in the alphanumeric file names and correlate to specpr record numbers designated in the manuscript figures in which they are shown. These transmission spectra were converted to absorbance in many of the figures. Spectra of talc, fibrous richterite amphibole, and serpentine are from well characterized samples from Feiser Mine, Ruby Mountains,...
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This dataset contains results from electron microprobe analyses for expanded and unexpanded vermiculite samples. These data are provide for samples of vermiculite ore, expanded vermiculite insulation, horticultural products, aggregate, and packing materials derived from mines near Enoree, South Carolina; Libby, Montana; Louisa, Virginia; Palabora, South Africa; Jiangsu, China; and Llano, Texas. An ASCII text file of results is provided in comma-separated by value (csv) format. The file has the name “vermiculite_probe_microanalyses_data.csv”.
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This Data Release includes information used to support numerical simulations of variably-saturated flow focused on measurement-based variability in soil-water retention properties for the U.S. Geological Survey's San Francisco Bay Area "BALT1" landslide monitoring site in the East Bay region of California, USA (see Thomas et al., 2018). The eight datasets are: (1) geologic and instrumentation logs recorded for BALT1 from May 2009 through March 2017, (2) collocated soil-moisture and soil-suction measurements collected at BALT1 from November 2010 through September 2016, (3) field-saturated hydraulic conductivity (infiltrometer) measurements collected at BALT1 in May 2017, (4) field-saturated hydraulic conductivity...
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Examination of food webs and trophic niches provide insight into organisms’ functional ecology, yet few studies have examined the trophodynamics within submarine canyons, where the interaction of morphology and oceanography influences food deposition. Stable isotope analysis and Bayesian ellipses documented deep-sea food web structure and trophic niches in Baltimore Canyon and the adjacent open slopes in the U.S. Mid-Atlantic Region. Results revealed isotopically diverse feeding groups, comprising approximately 5 trophic levels. Regression analysis indicated that consumer isotope data are structured by site (canyon vs. slope), feeding group, and depth. Benthic feeders were enriched in 13C and 15N relative to suspension...
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This dataset contains descriptions and analytical data (i.e., electron microprobe, X-ray diffraction, spectral reflectance, and scanning electron microprobe analyses) for unexpanded and expanded vermiculite samples. These data are provided for 52 samples of vermiculite attic insulation, horticultural products, aggregate, and packing materials derived from mines near Enoree, South Carolina; Libby, Montana; Louisa, Virginia; Palabora, South Africa; and Jiangsu, China collected from 2000 to 2016. Electron probe microanalysis and spectra of unexpanded ores from these locations and Llano, Texas are also given. Tables of electron microprobe and spectral absorption information are also included along with ascii listings...
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Mesopelagic fishes represent an important component of the marine food web due to their global distributions, high abundances and ability to transport organic material throughout a large part of the water column. This study combined stable isotope (SIA) and gut content analyses (GCA) to characterize the trophic structure of mesopelagic fishes in the north central Gulf of Mexico. Additionally this study examined whether mesopelagic fishes utilized chemosynthetic energy from cold seeps. Specimens were collected (9-25 August 2007) over three deep (>1000 m) cold seeps at discrete depths (surface to 1503 m) over the diurnal cycle. Gut content analyses classified 31 species (5 families) of mesopelagic fishes into 5 feeding...
Conservation of imperiled species is frequently challenged by insufficient knowledge of life history and the environmental factors that affect various life stages. The larvae (glochidia) of most freshwater mussels in the family Unionidae are obligate ectoparasites of fishes. We describe the early life history of the federally endangered Southern Kidneyshell, Ptychobranchus jonesi, and compare methods for estimating fecundity and conducting host trials on conglutinate-producing mussel species. Both the glochidial inoculation baths and direct feeding of conglutinates to Percina nigrofasciata, Etheostoma edwini, and Etheostoma fusiforme resulted in successful metamorphosis to the juvenile life stage. Ptychobranchus...
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Fire can be a significant driver of permafrost change in boreal landscapes, altering the availability of soil carbon and nutrients that have important implications for future climate and ecological succession. However, not all landscapes are equally susceptible to fire-induced change. As fire frequency is expected to increase in the high latitudes, methods to understand the vulnerability and resilience of different landscapes to permafrost degradation are needed. Geophysical and other field observations reveal details of both near-surface (less than 1 m) and deeper (greater than 1 m) impacts of fire on permafrost along 14 transects that span burned-unburned boundaries in different landscape settings within interior...
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Fire can be a significant driver of permafrost change in boreal landscapes, altering the availability of soil carbon and nutrients that have important implications for future climate and ecological succession. However, not all landscapes are equally susceptible to fire-induced change. As fire frequency is expected to increase in the high latitudes, methods to understand the vulnerability and resilience of different landscapes to permafrost degradation are needed. Geophysical and other field observations reveal details of both near-surface (less than 1 m) and deeper (greater than 1 m) impacts of fire on permafrost along 14 transects that span burned-unburned boundaries in different landscape settings within interior...
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Fire can be a significant driver of permafrost change in boreal landscapes, altering the availability of soil carbon and nutrients that have important implications for future climate and ecological succession. However, not all landscapes are equally susceptible to fire-induced change. As fire frequency is expected to increase in the high latitudes, methods to understand the vulnerability and resilience of different landscapes to permafrost degradation are needed. Geophysical and other field observations reveal details of both near-surface (less than 1 m) and deeper (greater than 1 m) impacts of fire on permafrost along 14 transects that span burned-unburned boundaries in different landscape settings within interior...
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This folder contains descriptions and analytical data (i.e., electron microprobe, X-ray diffraction, spectral reflectance, and scanning electron microprobe analyses) for unexpanded and expanded vermiculite samples. These data are provided for 52 samples of vermiculite attic insulation, horticultural products, aggregate, and packing materials derived from mines near Enoree, South Carolina; Libby, Montana; Louisa, Virginia; Palabora, South Africa; and Jiangsu, China collected from 2000 to 2016. X-ray diffraction data for a limited set of the 52 expanded vermiculite samples are also given in figures included in the sample description pdf files. Quantitative XRD diffractograms are included for an ore sample from each...
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The dataset contains broadband synthetic ground motion records for three events: 1) 1994 M6.7 Northridge, CA, 2) 1989 M7.0 Loma Prieta, CA, and 3) 1999 M7.5 Izmit, Turkey. For each event, 1D synthetic earthquake ground motion time histories are provided, based on four different methodologies: 1) Frankel, A. (2009). A constant stress-drop model for producing broadband synthetic seismograms: comparison with the next generation attenuation relations, Bull. Seism. Soc. Am. V.99, 664-680. 2) Hartzell, S., M. Guatteri, P. Martin Mai, P. Liu, and M. Fisk (2005). Calculation of broadband time histories of ground motion, part II: kinematic and dynamic modeling using theoretical Green’s functions and comparison with the 1994...
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The USGS Geologic Hazards Science Center (GHSC) in Golden, CO maintains a GIS server with services pertaining to various geologic hazard disciplines involving earthquakes and landslides. The online link provides an overview of the structure of this server and also outlines the GIS data it contains. The folders named eq (earthquakes), haz (earthquake hazards), and ls (landlsides) contain services with data associated with each discipline.
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This Data Release makes available measurements of phytoplankton species composition, abundance and cell size made on samples collected in San Francisco Bay (CA) from April 1992 through March 2014. Phytoplankton samples were collected at 31 stations along a 145-km transect where the variability of salinity, temperature, turbidity and nutrient concentrations reflected a broad range of environmental factors that regulate phytoplankton growth and abundance (map of sampling locations is available on the project website at: https://sfbay.wr.usgs.gov/access/wqdata/overview/wherewhen/stnmap.html). Whole water samples were preserved with acid Lugol’s solution, and 2 to 50 ml aliquots were settled in chambers for 6 to 24...
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A Finite Fault is a modeled representation of the spatial extent, amplitude and duration of fault rupture (slip) of an earthquake, and is generated via the inversion of teleseismic body waveforms and long period surface waves. It may indicate that a location of major fault-slip and source of seismic energy has occurred at a significant distance from the earthquake epicenter, which is the location on the fault where the earthquake rupture nucleated. For many earthquakes, the preferred model represents the distribution of slip on one of the two alternative fault-planes that are implied by the earthquake moment-tensor. For some earthquakes, the seismographic data are fit equally well by models involving slip on either...
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Sediment hosted gold deposits in Nevada were first mined in the 1960s from open pit mines with large tonnage and low grade resources. Since that time, continuing exploration and discovery have identified extraordinary resources, and together these deposits now form the second-largest gold endowment on Earth, surpassed only by the Witwatersrand Gold Fields of South Africa. The data herein are part of a larger U.S. Geological Survey (USGS) project to develop an updated geospatial database of mines, mineral deposits and mineral regions in the United States. The point and polygon layers within this database represent locations of mines, mineral occurrences (which includes deposits and prospects), and mining...
Categories: Data; Types: ArcGIS REST Map Service, ArcGIS Service Definition, Downloadable, Map Service; Tags: mineral commodity, Nevada, United States, Elko County, barite, All tags...


map background search result map search result map Fire impacts on permafrost in Alaska: Geophysical and other field data collected in 2015 Trophic structure of mesopelagic fishes in the Gulf of Mexico revealed by gut content and stable isotope analyses Spectroscopy of Expanded Vermiculite Products and Insulation Borehole Nuclear Magnetic Resonance Inverted Models; Alaska, 2015 Electrical Resistivity Tomography Inverted Models; Alaska, 2015 Expanded Vermiculite Sample Descriptions Table of Electron Probe Microanalyses of Vermiculite Samples Food-web dynamics and isotopic niches in deep-sea communities residing in a submarine canyon and on the adjacent open slopes Spectra Used in Figures Field data used to support hydrologic modeling for the U.S. Geological Survey's San Francisco Bay Area "BALT1" landslide monitoring site Mines, Mineral Occurrences, and Mining Districts in the Carlin Area, Nevada Collection, analysis, and age-dating of sediment cores from salt marshes on the south shore of Cape Cod, Massachusetts, from 2013 through 2014 Field data used to support hydrologic modeling for the U.S. Geological Survey's San Francisco Bay Area "BALT1" landslide monitoring site Collection, analysis, and age-dating of sediment cores from salt marshes on the south shore of Cape Cod, Massachusetts, from 2013 through 2014 Trophic structure of mesopelagic fishes in the Gulf of Mexico revealed by gut content and stable isotope analyses Fire impacts on permafrost in Alaska: Geophysical and other field data collected in 2015 Borehole Nuclear Magnetic Resonance Inverted Models; Alaska, 2015 Electrical Resistivity Tomography Inverted Models; Alaska, 2015 Spectroscopy of Expanded Vermiculite Products and Insulation Expanded Vermiculite Sample Descriptions Table of Electron Probe Microanalyses of Vermiculite Samples Spectra Used in Figures