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Two dams on the Elwha River, Washington State, USA trapped over 20 million m3 of sediment, reducing downstream sediment fluxes and contributing to erosion of the river's coastal delta. The removal of the Elwha and Glines Canyon dams between 2011 and 2014 induced massive increases in river sediment supply and provided an unprecedented opportunity to examine the response of a delta system to changes in sediment supply. The U.S. Geological Survey (USGS) developed an integrated research program aimed at understanding the ecosystem responses following dam removal. The research program included repeated surveys of beach topography, nearshore bathymetry, and surface sediment grain size to quantify changes in delta morphology...
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The files consist of two types: tabulated data files and graphical map files. Data files consist of six .csv files, representing six experiment dates (2016_06_14, 2016_16_15, 2016_18_15, 2016_16_21, 2016_16_22, 2016_16_23). Each of these files contains multiple columns of data, with each column representing either a time measurement or the value of a physical quantity measured at that time (e.g., flow depth, pore pressure, normal stress, etc.). Map files consist of six .pdf files, each representing an experiment date listed above. The maps show the thickness of the sediment deposited onto the runout pad after each experiment. Sediment thickness was determined using photogrammetery software from Adam Technology.
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This data release includes approximately 1,032 km of marine single-channel seismic-reflection data collected by the U.S. Geological Survey on a research cruise (USGS survey 2014-632-FA) in July and August, 2014, between Point Sal and Refugio State Beach. The dataset includes 168 profiles, most of which were collected on tracklines roughly perpendicular to the coast at 1 km line spacing; additional profiles were collected on coast-parallel tie lines. These data were acquired to support the California Seafloor Mapping Program and USGS Geologic Hazards projects. Seismic-reflection data were collected using a minisparker system that creates an acoustic signal by discharging an electrical pulse between electrodes and...
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New Zealand’s Alpine Fault (AF) ruptures quasi-periodically in large-magnitude earthquakes. Paleoseismological evidence suggests that about half of all recognized AF earthquakes terminated at the boundary between the Central and South Westland sections of the fault. There, fault geometry and the polarity of uplift change. The South Westland AF exhibits oblique-normal fault motion on a structure oriented 055/82SE that, for at least 35 km along strike, contains saponite-rich principal slip zone gouges. New hydrothermal friction experiments reveal that the saponite fault gouge is frictionally weak, exhibiting friction coefficients between =0.12 and =0.16 for a range of temperatures (T=25–210 C) and effective normal...
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This data release presents beach topography and nearshore bathymetry data from repeated surveys in northern Monterey Bay, California to document changes in shoreline position and coastal morphology as they relate to episodic (storms), seasonal, and interannual and longer (e.g. El Niño) processes. The ongoing monitoring program was initiated in October 2014 with semi-annual surveys performed in late summer (September or October) and Spring (March). Nearshore bathymetry and topography data were collected along a series of shore-perpendicular transects spaced primarily at 50-250 m intervals between Santa Cruz and Moss Landing, California (fig. 1). The transects were located along sandy stretches of the coastline...
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In March 2015, the U.S. Geological Survey acquired seismic reflection and refraction data along an approximately 2.8-km-long profile across northwest-trending San Andreas Fault splays located at the Dos Palmas Preserve east of Salton Sea. To acquire the reflection and refraction data, we collocated shots and geophones, spaced every 3 m along the profile. We used 933 SercelTM L40A P-wave (40-Hz vertical-component) geophones with a sensitivity of 22.34 volts/meter/second to record 925 P-wave shots. We generated P-wave data using one of two active sources: 400-grain Betsy-SeisgunTM shots at approximately every 90 m and a 3.5-kg sledgehammer and steel plate combination at every 3 m between the seisgun shots. All data...
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Gravity data were collected from 2006 through 2015 to assist in mapping subsurface geology in the southern San Luis Basin, northern New Mexico. This data release provides principal facts for 566 new gravity stations that were acquired to fill in gaps in the existing public gravity data coverage.
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Airborne geophysical surveys were conducted in the eastern Adirondacks from Dec. 7, 2015 - Dec. 21, 2015, by Goldak Airborne Surveys. The area was flown along a draped surface with a nominal survey height above ground of 200 meters. The flight line spacing was 250 meters for traverse lines and 2500 meters for control lines. Here we present downloadable magnetic and radiometric (gamma spectrometry) data from those surveys as image (Geotiff) and flight line data (csv format). Background The Eastern Adirondacks region was known for iron mining in the 1800's and 1900's but it also contains deposits of rare earth minerals. Rare earth minerals are used in advanced technology such as in cell phones, rechargeable batteries...
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This digital elevation model provides a tool for calibrating tsunami risk to observations of the 1945 Makran tsunami in Karachi Harbour. The DEM bathymetry is derived from soundings made mainly during the first eight years after the tsunami. Although deficient in portraying intertidal backwaters and upland topography, the DEM accurately depicts the sheltered setting of one of the two tide gauges that recorded the 1945 tsunami.
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The U.S. Geological Survey (USGS) collected high-resolution multichannel minisparker and single-channel chirp seismic-reflection data in November 2014, in the offshore Catalina and Santa Cruz basins, which are surrounded by several of the southern California Channel Islands. The survey was designed to image faults and folds associated with movement on the numerous faults in offshore southern California, including the Catalina, Catalina Ridge, San Clemente, and San Diego Trough faults, as well as several other unnamed fault zones. These data can be used to update the USGS Quaternary fault database and in shaking hazard models developed by the Working Group on California Earthquake Probabilities. In addition, the...
Categories: Data; Tags: Geophysics
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High-resolution multichannel minisparker and chirp seismic-reflection data were collected in August of 2015 to explore marine geologic hazards of inland waterways of southeastern Alaska. Sub-bottom profiles were acquired in the inland waters between Glacier Bay and Juneau, including Cross Sound and Chatham Strait. High-resolution seismic-reflection profiles were acquired to assess evidence for active seabed faulting and submarine landslide hazards. The data were collected aboard the U.S. Geological Survey R/V Alaskan Gyre. Chirp data were acquired using a tow-fish Edgetech 512 chirp subbottom profiler, and multichannel (mcs) minisparker data were acquired using a 500-Joule minisparker source and a 48-channel Geometrics...
Categories: Data; Tags: Geophysics
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Subduction zones are home to the most seismically active faults on the planet. The shallow megathrust interface of subduction zones host our largest earthquakes, and are the only faults capable of M9+ ruptures. Despite these facts, our knowledge of subduction zone geometry - which likely plays a key role in determining the spatial extent and ultimately the size of subduction zone earthquakes - is incomplete. Here we calculate the three- dimensional geometries of all active global subduction zones. The resulting model - Slab2 - provides for the first time a comprehensive geometrical analysis of all known slabs in unprecedented detail. ##### This distribution includes models of three-dimensional slab geometry under...
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This dataset includes the audio-magnetotelluric (AMT) sounding data collected in 2009 in and near the San Luis Basin, New Mexico. The U.S. Geological Survey conducted a series of multidisciplinary studies, including AMT surveys, in the San Luis Basin to improve understanding of the hydrogeology of the Santa Fe Group and the nature of the sedimentary deposits comprising the principal groundwater aquifers of the Rio Grande rift. The shallow unconfined and the deeper confined Santa Fe Group aquifers in the San Luis Basin are the main sources of municipal water for the region. The population of the San Luis Basin region is growing rapidly and water shortfalls could have serious consequences. Future growth and land management...
Categories: Data; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, Shapefile; Tags: AMT, Cerro, Cerro De La Olla, GGGSC, GPS measurement, All tags...
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This part of the data release presents a digital elevation model (DEM) created from bathymetry data collected on February 1, 2011, in the Sacramento River from the confluence of the Feather River to Knights Landing. The data were collected by the USGS Pacific Coastal and Marine Science Center (PCMSC) team with collaboration and funding from the U.S. Army Corps of Engineers. This project used interferometric sidescan sonar to characterize the riverbed and channel banks along a 12 mile reach of the Sacramento River, California (River Mile 79 through River Mile 91) to aid in the understanding of fish response to the creation of safe habitat associated with levee restoration efforts in two 1.5 mile reaches of the Sacramento...
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Here we present surface current results from a physics-based, 3-dimensional coupled ocean-atmosphere numerical model that was generated to understand coral larval dispersal patterns in Maui Nui, Hawaii, USA. The model was used to simulate coral larval dispersal patterns from a number of existing State-managed reefs and large tracks of reefs with high coral coverage that might be good candidates for marine-protected areas (MPAs) during 8 spawning events during 2010-2013. The goal of this effort is to provide geophysical data to help provide guidance to sustain coral health in Maui Nui, Hawaii, USA. Each model output run is available as a netCDF file with self-contained attribute information. Each file name is appended...
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Samples, sample depths, paleomagnetism, and magnetic susceptibility parameters are recorded for BP-3-USGS well, San Luis Valley, Southwestern Colorado.
First release: 2015 Revised: July 2017 (ver. 2.0) Approximately 95 square kilometers of area was mapped with multibeam sonar. The survey expanded the extent of mapping data collected by Solmar Hydro Inc. in 2013 under a contract with WindFloat Pacific. When added to the Solmar Hydro data the total area mapped is approximately 140 square kilometers, lying in Federal waters on the shelf offshore of Coos Bay of interest for renewable energy (OCS-P lease blocks 6523, 6524, 6573, 6574, 6623, 6624, 6673, and 6674). Water depths range from 300 to 500 meters and are within the effective depth range of the Reson 7111. The seabed in his area is composed of sand and mud, with rocky outcrops on tectonically uplifted features....
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The collection of borehole geophysical logs data was conducted by the U.S. Geological Survey South Atlantic Water Science Center in the vicinity of the Cristex Drum National Priorities List Superfund Site near Oxford, North Carolina, during January through March 2016. In an effort to assist the U.S. Environmental Protection Agency in the development of a conceptual groundwater model for the assessment of current contaminant distribution and future migration of contaminants, borehole geophysical log and image data collection, which included the delineation of more than 150 subsurface features (primarily fracture orientations) in 3 open borehole wells.
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Airborne electromagnetic (AEM) and magnetic survey data were collected during February 2016 along 300 line kilometers in the western Yukon Flats near Stevens Village, Alaska. Data were acquired with the CGG RESOLVE frequency-domain helicopter-borne electromagnetic systems together with a Scintrex Cesium Vapour CS-3 magnetometer. The AEM average depth of investigation is about 100 m. The survey was flown at a nominal flight height of 30 m above terrain along widely spaced reconnaissance lines. This data release includes raw and processed AEM data and laterally-constrained inverted resistivity depth sections along all flight lines. This release also includes unprocessed and processed magnetic data that has been drift...


map background search result map search result map Physics-based numerical circulation model outputs of ocean surface circulation during the 2010-2013 summer coral-spawning seasons in Maui Nui, Hawaii, USA Airborne Geophysical Surveys over the Eastern Adirondacks, New York State Principal facts of gravity data in the southern San Luis Basin, northern New Mexico Marine geophysical data—Point Sal to Refugio State Beach, southern California Geophysical Logging at the Cristex Drum National Priorities List Superfund Site near Oxford, North Carolina Bathymetry and topography data from the Elwha River delta, Washington, May 2011 Bathymetric DEM of the Sacramento River, from the Feather River to Knights Landing, California in February 2011 Airborne electromagnetic and magnetic survey data and inverted resistivity models, western Yukon Flats, Alaska, February 2016 Sensor data from debris-flow experiments conducted in June, 2016, at the USGS debris-flow flume, HJ Andrews Experimental Forest, Blue River, Oregon Data release for a paleomagnetic age estimate for the draining of ancient Lake Alamosa, San Luis Valley, south-central Colorado, U.S.A. Beach topography and nearshore bathymetry of northern Monterey Bay, California Audiomagnetotelluric sounding data, stations 1-9, Taos Plateau Volcanic Field, New Mexico, 2009 Data for Frictional Properties and 3-D Stress Analysis of the Southern Alpine Fault, New Zealand (2013) 2015 high resolution seismic acquisition at Dos Palmas Preserve, Mecca, California Bathymetric and topographic grid intended for simulations of the 1945 Makran tsunami in Karachi Harbour Sensor data from debris-flow experiments conducted in June, 2016, at the USGS debris-flow flume, HJ Andrews Experimental Forest, Blue River, Oregon Bathymetry and topography data from the Elwha River delta, Washington, May 2011 2015 high resolution seismic acquisition at Dos Palmas Preserve, Mecca, California Geophysical Logging at the Cristex Drum National Priorities List Superfund Site near Oxford, North Carolina Bathymetric DEM of the Sacramento River, from the Feather River to Knights Landing, California in February 2011 Bathymetric and topographic grid intended for simulations of the 1945 Makran tsunami in Karachi Harbour Data for Frictional Properties and 3-D Stress Analysis of the Southern Alpine Fault, New Zealand (2013) Audiomagnetotelluric sounding data, stations 1-9, Taos Plateau Volcanic Field, New Mexico, 2009 Beach topography and nearshore bathymetry of northern Monterey Bay, California Airborne electromagnetic and magnetic survey data and inverted resistivity models, western Yukon Flats, Alaska, February 2016 Marine geophysical data—Point Sal to Refugio State Beach, southern California Principal facts of gravity data in the southern San Luis Basin, northern New Mexico Physics-based numerical circulation model outputs of ocean surface circulation during the 2010-2013 summer coral-spawning seasons in Maui Nui, Hawaii, USA