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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.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Avalanche,
Blue River, Oregon,
Debris-flow,
Geomorphology,
Geophysics,
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...
This data release provides access to a low-altitude, aeromagnetic survey over parts of Missouri, Arkansas, and Tennessee, an area centered about 100 km north of Memphis, Tennessee. The survey covers parts of the southern arm of the New Madrid seismic zone, the northwestern margin of the Reelfoot rift, the Blytheville arch, and the Commerce geophysical lineament (reference: Langenheim, V.E., and Hildenbrand, T.G., 1997, Geological Society of America Bulletin, v. 109, p. 580). The survey is underlain by Paleocene and younger sediments, consisting of silt, clay, sand, and gravel. Plutons and other intrusive rocks lie at depth. These data were acquired between July 12 and July 28, 2013, by EDCON-PRJ, Inc., working under...
This data release provides access to a low-altitude, aeromagnetic survey of a part of south-central Washington centered approximately 30 km east of Yakima and referred to as the Hanford aeromagnetic survey. The survey includes the city of Richland, numerous smaller communities, and the Hanford Site (https://www.hanford.gov). The Hanford aeromagnetic survey extends from the Columbia Plateau westward to the Cascade Range and illuminates magnetic anomalies associated with folds and faults of the Yakima folds, including the Toppenish Ridge, Ahtanum Ridge, Umtanum Ridge, Boyleston Mountain, Rattlesnake Mountain, Saddle Mountains, and Frenchman Hills anticlines. These data were acquired during September and October, 2009,...
This data release provides access to a low-altitude, aeromagnetic survey of a part of south-central Washington and north-central Oregon. The survey extends from the Blue Mountains westward to the Cascade Range and covers the Oregon cities of The Dalles, Hermiston, and Milton Freewater and the Washington cities of Richland, Pasco, Kennewick, and Walla Walla. Data were acquired during the summer of 2010 by Goldak Airborne Surveys working under contract to the U.S. Geological Survey. Total magnetic field values were acquired using a fixed-wing aircraft flown at a target elevation of 150 m above terrain (305 m over urban areas) and along flight lines and tie lines spaced 400 m and 4000 m apart, respectively. Flight...
Fine-grained sediments, or “fines,” are nearly ubiquitous in natural sediments, even in the predominantly coarse-grained sediments that host gas hydrates. Fines within these sandy sediments can be mobilized and subsequently clog flow pathways while methane is being extracted from gas hydrate as an energy resource. Using two-dimensional (2D) micromodels to test the conditions in which clogging occurs provides insights for choosing production operation parameters that optimize methane recovery in the field. During methane extraction, several processes can alter the mobility and clogging potential of fines: (1) fluid flow as the formation is depressurized to release methane from gas hydrate, (2) shifting pore-fluid...
Categories: Data;
Tags: 2D micromodel,
Bay of Bengal,
Department of Civil and Environmental Engineering,
Geophysics,
Indian Ocean,
Lake Poinsett is a 260-hectare (640 acres) lake located on Crowley’s Ridge in northeastern Arkansas, approximately 6 km southeast of Harrisburg, Arkansas within Poinsett County. The lake was built for recreation by the Arkansas Highway Department in 1960 by constructing a roughly 800-meter dam across the southern boundary of the Distress Creek watershed. The dam is currently operated by the Arkansas Game and Fish Commission (AGFC). AGFC and Arkansas Natural Resources Commission (ANRC) plan to drain the lake to allow access for a series of bank stabilization and dam safety improvements. Because none of the original blueprints exist, AGFC asked the U.S. Geological Survey (USGS) to conduct a series of differential...
Categories: Data;
Tags: Arkansas,
Crowley's Ridge,
Electrical Resistivity,
Frequency Domain Electromagnetics,
GNSS Survey,
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...
Large numerical grid used for finite element and finite volume analysis of induced seismicity in Paradox Basin. The grid construction used the boundaries of three sub-horizontal surfaces; the topography, and the top and bottom of the production formation is determined from drilling and seismic reflection profiling, yielding the surface topography and thickness variations in these data throughout the domain. The cell dimensions in the north and east directions are 200 m and the horizontal gridlines are oriented north-south and east-west. There are 245 elements in the east west direction, 241 elements in the north south direction, and 31 elements in the vertical, extending from the surface to 15 km depth. The grid...
The U.S. Geological Survey (USGS) collected over 1,840 physical property measurements on selected plutons in the Great Basin, primarily in California and Nevada. Data include station identifier, geographic coordinates, rock type, density, magnetic susceptibility, remanent magnetization, declination, and inclination where available. Data are presented in ASCII format and include density and magnetic property data in pluton_data.csv, a data dictionary describing the data fields in data_dictionary.csv, and a rock data dictionary listing rock types in rock_dictionary.csv. Preliminary results and interpretation were described by Ponce and others (2010) and some samples are from Sikora and others (1991). References: Ponce,...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Density,
Energy Resources,
Geophysical studies,
Geophysics,
Great Basin, parts of California, Nevada, Oregon, Utah, and Arizona,
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...
The 2018 Kīlauea eruption and caldera collapse generated intense cycles of seismicity tied to repeated large seismic (Mw ~5) collapse events associated with magma withdrawal from beneath the summit. To gain insight into the underlying dynamics and aid eruption response, we applied waveform-based earthquake detection and double-difference location as the eruption unfolded. Here, we augment these rapid results by grouping events based on patterns of correlation-derived phase polarities across the network. From April 29 to August 6, bracketing the eruption, we used ~2800 events cataloged by the Hawaiian Volcano Observatory to detect and precisely locate 44,000+ earthquakes. Resulting hypocentroids resolve complex,...
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...
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...
In October 2016, we acquired an approximately 15-km-long seismic profile along a linear transect across the East Bay region of the San Francisco Bay area. Our goal was to image previously unknown strands of the Hayward Fault zone and to better delineate the structure and geometry of the main trace of the Hayward Fault. Our profile started near the southern border of San Leandro, California at the San Francisco Bay shoreline, trended ENE through the northern edge of Castro Valley, California, and ended approximately 5 km WSW of San Ramon, California. The data were analyzed using refraction tomography modeling, reflection processing, and guided-wave analysis. The analyzed data are presented in separate reports by...
Categories: Data;
Tags: Geophysics,
Hayward,
San Francisco Bay Area,
Seismology,
USGS Science Data Catalog (SDC),
This data release contains field data for two P-wave seismic reflection profiles acquired across the Warm Springs Valley fault zone, part of the Northern Walker Lane, NV. The dataset consists of high-resolution seismic reflection field records in .segy format, shot coordinates in .csv format, and observers’ logs in .pdf format. The high-resolution seismic profiles are approximately 4 km long. The northern profile (Warm Springs Line 1) is oblique to a prominent fault bounded ridge. The southern profile (Warm Springs Line 2) crosses the northern end of Warm Springs Valley and is nearly co-located with COCORP profile NV-08. To obtain the seismic profiles, we used a 230 kg accelerated weight drop source and a nominal...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Fault,
Geophysics,
Hazards,
Nevada,
Seismic,
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,
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.
Categories: Data;
Types: Citation,
Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Geophysics,
Questa,
Rio Arriba County,
Taos,
Taos County,
The U.S. Geological Survey (USGS) has been engaged in airborne electromagnetics (AEM) since the 1970s, playing a role in the development of early acquisition systems, developing calibration methods, refining standards for data acquisition, improving data processing, modeling, and interpretation methods, and expanding the range of AEM applications. However, USGS AEM survey visibility and data accessibility has not advanced as rapidly as our use of the technique. This data release catalogs AEM surveys in the United States that have contributed to studies under USGS programs including Water, Geologic Mapping, Minerals, Energy, Environmental Health, Ecosystems, Hazards, and Climate. This dataset contains locations for...
Categories: Data;
Types: ArcGIS REST Map Service,
ArcGIS Service Definition,
Downloadable,
Map Service;
Tags: Alabama,
Arizona,
Arkansas,
California,
Colorado,
This dataset accompanies planned publication 'Determining fault geometry through the transport-parallel distribution of thermochronometer cooling ages'. The Ar/Ar data is for samples that record the thermal history of the area. The geochronology provides time constraints for the thermal histories studied in the manuscript. Samples were collected from Nepal, overseen by Nadine McQuarrie (University of Pittsburgh), who sent them to the USGS Denver Argon Geochronology Laboratory for Ar/Ar analysis.
Categories: Data;
Tags: 40Ar/39Ar,
Argon Geochronology Laboratory,
GGGSC,
Geochemistry,
Geology, Geophysics, and Geochemistry Science Center,
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