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In spring and summer 2017, the U.S. Geological Survey’s Gas Hydrates Project conducted two cruises aboard the research vessel Hugh R. Sharp to explore the geology, chemistry, ecology, physics, and oceanography of sea-floor methane seeps and water column gas plumes on the northern U.S. Atlantic margin between the Baltimore and Keller Canyons. Split-beam and multibeam echo sounders and a chirp subbottom profiler were deployed during the cruises to map water column backscatter, sea-floor bathymetry and backscatter, and subsurface stratigraphy associated with known and undiscovered sea-floor methane seeps. The first cruise, known as the Interagency Mission for Methane Research on Seafloor Seeps and designated as field...
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Chirp data were collected by the U.S. Geological Survey in September of 2013 in Port Valdez, Alaska. Data were collected aboard the USGS R/V Alaskan Gyre during field activity G-01-13-GA, using an EdgeTech SB-512i sub-bottom profiler. Sub-bottom acoustic penetration spans several tens of meters and is variable by location.
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Multichannel minisparker and boomer seismic-reflection and chirp sub bottom data were collected by the U.S. Geological Survey in September of 2013 in Port Valdez, Alaska. Data were collected aboard the USGS R/V Alaskan Gyre during field activity G-01-13-GA. Sub-bottom acoustic penetration spans several hundreds of meters and is variable by location. High-resolution multichannel seismic-reflection data were acquired to support the U.S. Geological Survey Alaska coastal and marine hazards project to explore the sedimentary structure of tsunamigenic landslide deposits around an IODP drill site in Port Valdez. These data and information are intended for science researchers, students from elementary through college, policy...
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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
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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Surface-based 2D electrical resistivity tomography (ERT) surveys were used to investigate the distribution of permafrost at wetland sites on the alluvial plain north of the Tanana River, 20 km southwest of Fairbanks, Alaska, in June and September 2014. The sites contained habitat types characteristic of interior Alaska, including thermokarst bog, forested permafrost plateau, and a rich fen. These habitats range from treed to open and vary in groundcover vegetation and peat thickness. Individual surveys used a cable with 56 electrodes at 2-m spacing. At a fen site, ERT surveys were performed across a mixed spruce forest area across a vegetation gradient into an open fen area. At a bog site,surveys were performed...
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Passive seismic data collection was done northwest of the Air Force Research Laboratory (AFRL) at Edwards Air Force Base using the horizontal-to-vertical spectral ratio (HVSR) technique. HVSR surveys were done at 43 locations between May and September 2018 to refine the understanding of the bedrock-alluvial aquifer transition zone downgradient from the AFRL. Specifically, the data were collected to help determine the depth to bedrock. The HVSR method is a passive seismic technique that uses a three-component seismometer to measure the vertical and horizontal components of ambient seismic noise. Seismic noise in the range of ~0.1 to 1 Hertz (Hz) is caused by ocean waves, large regional storms, and tectonic sources....
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Seismicity catalogs, gridded seismic hazard curve data, gridded ground motion data, and mapped gridded ground motion values are available for the 2002 National Seismic Hazard Model for the Conterminous U.S. Seismicity catalogs are available for the western U.S. (in Mw) and central and eastern U.S. (in mb). Probabilistic seismic hazard data and maps of the conterminous U.S. for peak ground acceleration (PGA) and 0.1, 0.2, 0.3, 0.5, 1.0 and 2.0 second spectral acceleration at probability levels of 2 percent in 50 years (annual probability of 0.000404) and 10 percent in 50 years (annual probability of 0.0021), assuming firm rock soil conditions at 760 m/s, are available. Hazard was calculated on a 0.1 degree by 0.1...
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Gridded ground motion data and mapped gridded ground motion values are available for the 1999 Alaska Seismic Hazard Model. Probabilistic seismic hazard data and maps of Alaska and the Aleutians for peak ground acceleration (PGA) and 0.2, 0.3, and 1.0 second spectral acceleration at probability levels of 2 percent in 50 years (annual probability of 0.000404) and 10 percent in 50 years (annual probably of 0.0021), assuming firm rock soil conditions at 760 m/s, are available. Development of the 1999 Alaska Seismic Hazard Model is documented in the USGS Open-File Report 99-36 (https://doi.org/10.3133/ofr9936). This dataset is considered a legacy dataset. The original dataset was released at the time of publication...
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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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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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I use template matching and precise relative relocation techniques to develop a high-resolution earthquake catalog for the initial portion of the 2019 Ridgecrest earthquake sequence, from July 4-16, encompassing the foreshock sequence and the first 10+ days of aftershocks following the Mw 7.1 mainshock. Using 13,525 routinely cataloged events as waveform templates, I detect and precisely locate a total of 34,091 events. Precisely located earthquakes reveal numerous cross-cutting fault structures with dominantly perpendicular SW- and NW-strikes. Foreshocks of the Mw 6.4 event appear to align on a NW-striking fault. Aftershocks of the Mw 6.4 event suggest that it further ruptured this NW-striking fault, as well as...
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Floating transient electromagnetic (FloaTEM) data were acquired on the Upper Delaware River during December 2018. During the survey, approximately 10 line-kilometers were collected in the Upper Delaware River, near USGS boring 12008-14 (https://webapps.usgs.gov/GeoLogLocator/#!/search) near Barryville, New York study area. Data were collected by members of the U.S. Geological Survey, Hydrogeophysics Branch, New England Water Science Center, and the National Park Service UPDE. FloaTEM data acquired along the Delaware River in Sullivan County, in New York, were collected to test a new continuous water-borne transient electromagnetic data collection platform, and to characterize the subsurface resistivity structure....
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The original time series and cross power data were stored in Binary format on 3.5" disks until further conversion was needed. To convert the time series and cross power data to a format that can be used for modeling, the original binary files were converted to ASCII format using Basic 4.0 code and associated subroutines (see Magnetotelluric_Original-Code_Binary-to-Ascii.txt and Magnetotelluric_Original-Code_Binary-to-Ascii-Subroutines.txt attached to the binary data ScienceBase item). The DaR project used these converted ASCII format files to create the EDI format files included in this data release. The binary data are considered the original data for the magnetotelluric survey, therefore, they are provided with...
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This dataset consists of 42 magnetotelluric (MT) stations collected in 2017 in the Northwest Geysers, CA. The U.S. Geological Survey acquired these data as part of a project to image the heat source in the Northwest Geysers. Support was from the U.S. Geological Survey's Volcano Hazards Program.
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This dataset consists of 42 magnetotelluric (MT) stations collected in 2017 in the Northwest Geysers, CA. The U.S. Geological Survey acquired these data as part of a project to image the heat source in the Northwest Geysers. Support was from the U.S. Geological Survey's Volcano Hazards Program.
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This dataset consists of 42 magnetotelluric (MT) stations collected in 2017 in the Northwest Geysers, CA. The U.S. Geological Survey acquired these data as part of a project to image the heat source in the Northwest Geysers. Support was from the U.S. Geological Survey's Volcano Hazards Program.
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This dataset consists of 42 magnetotelluric (MT) stations collected in 2017 in the Northwest Geysers, CA. The U.S. Geological Survey acquired these data as part of a project to image the heat source in the Northwest Geysers. Support was from the U.S. Geological Survey's Volcano Hazards Program.
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This dataset includes audiomagnetotelluric (AMT) sounding data collected in July 2018 in the Silverton Caldera complex, Colorado, in the Southern Rocky Mountain Volcanic Field, by the U.S. Geological Survey (USGS). Along with geologic mapping, airborne magnetics, airborne electromagnetics, and magnetotellurics, the USGS collected AMT data at 24 sites along four profiles ranging from 3 to 6 kilometers in length across the north-western structural margin of the Silverton caldera in Mineral Basin (MB01-MB05), across the south-eastern margin of the caldera along Cunningham Creek (CC01-CC05), within the caldera in Eureka Graben (EG01-EG05), and within the caldera along upper Cement Creek near the Gold King mine (GK01-GK09).
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This dataset includes audiomagnetotelluric (AMT) sounding data collected in July 2018 in the Silverton Caldera complex, Colorado, in the Southern Rocky Mountain Volcanic Field, by the U.S. Geological Survey (USGS). Along with geologic mapping, airborne magnetics, airborne electromagnetics, and magnetotellurics, the USGS collected AMT data at 24 sites along four profiles ranging from 3 to 6 kilometers in length across the north-western structural margin of the Silverton caldera in Mineral Basin (MB01-MB05), across the south-eastern margin of the caldera along Cunningham Creek (CC01-CC05), within the caldera in Eureka Graben (EG01-EG05), and within the caldera along upper Cement Creek near the Gold King mine (GK01-GK09).


map background search result map search result map Magnetotelluric Data from the San Andreas Fault, Parkfield CA, 1990: Binary Data Data for Frictional Properties and 3-D Stress Analysis of the Southern Alpine Fault, New Zealand (2013) Permafrost Mapping in Two Wetland Systems North of the Tanana River in Interior Alaska 2014 Audiomagnetotelluric sounding data in the Silverton Caldera complex, Colorado, 2018; Station AMTCC04 Audiomagnetotelluric sounding data in the Silverton Caldera complex, Colorado, 2018; Station AMTGK07 station gz15 station gz24 station gz49 station gz50 Data Release for the 2002 National Seismic Hazard Model for the Conterminous U.S. Marine Geophysical Data Collected to Support Methane Seep Research Along the U.S. Atlantic Continental Shelf Break and Upper Continental Slope Between the Baltimore and Keller Canyons During U.S. Geological Survey Field Activities 2017-001-FA and 2017-002-FA Chirp, multichannel minisparker, and boomer seismic-reflection data from USGS field activity G-01-13-GA collected in Port Valdez, Alaska, in September 2013 Chirp seismic-reflection data from USGS field activity G-01-13-GA collected in Port Valdez, Alaska, in September 2013 Horizontal-to-Vertical Seismic Ratio Passive-Seismic Data Collected at Edwards Air Force Research Laboratory, Antelope Valley, California, 2018 Floating transient electromagnetic (FloaTEM) surveys in the Delaware River near Barryville, New York Permafrost Mapping in Two Wetland Systems North of the Tanana River in Interior Alaska 2014 Horizontal-to-Vertical Seismic Ratio Passive-Seismic Data Collected at Edwards Air Force Research Laboratory, Antelope Valley, California, 2018 Data for Frictional Properties and 3-D Stress Analysis of the Southern Alpine Fault, New Zealand (2013) Magnetotelluric Data from the San Andreas Fault, Parkfield CA, 1990: Binary Data Floating transient electromagnetic (FloaTEM) surveys in the Delaware River near Barryville, New York Marine Geophysical Data Collected to Support Methane Seep Research Along the U.S. Atlantic Continental Shelf Break and Upper Continental Slope Between the Baltimore and Keller Canyons During U.S. Geological Survey Field Activities 2017-001-FA and 2017-002-FA Data Release for the 2002 National Seismic Hazard Model for the Conterminous U.S.