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High-resolution multichannel minkisparker seismic-reflection (MCS) profiles were collected by the U.S. Geological Survey in September and October of 2016 from the northern portion of the Santa Barbara Basin offshore southern California. Data were collected aboard the USGS R/V Parke Snavely and NOAA R/V Shearwater during field activity 2016-666-FA. Data were acquired to support USGS geologic hazards projects to aide hazard assessment within the Santa Barbara Basin. High-resolution multichannel minisparker seismic-reflection, multibeam-bathymetry and acoustic-backscatter data were collected to investigate the causes and consequences of submarine landslides in the Santa Barbara Basin. These data and information are...
The U. S. Geological Survey (USGS) makes long-term seismic hazard forecasts that are used in building codes. The hazard models usually consider only natural seismicity; non-tectonic (man-made) earthquakes are excluded because they are transitory or too small. In the past decade, however, thousands of earthquakes related to underground fluid injection have occurred in the central and eastern U.S. (CEUS), and some have caused damage. In response, the USGS is now also making short-term forecasts that account for the hazard from these induced earthquakes. Seismicity statistics are analyzed to develop recurrence models, accounting for catalog completeness. In the USGS hazard modeling methodology, earthquakes are counted...
This data release consists of three geophysical data sets measured in the lower Guadalupe River channel, south-central Texas, and one supplementary geophysical data set measured in a laboratory. The lower Guadalupe River is incised into the outcrop of the Carrizo-Wilcox aquifer in south-central Texas. The river and the aquifer are hydraulically connected across the outcrop, although the connectivity is obscured by alluvium and surface-water and groundwater exchange dynamics are currently poorly understood. The data sets were therefore produced to investigate surface-water and groundwater exchange dynamics between the lower Guadalupe River and the Carrizo-Wilcox aquifer, and consist of (1) a 14.86 kilometer (km)...
Categories: Data;
Tags: Dipole,
Electric Resistivity Tomography,
Geomorphology,
Geophysics,
Geophysics,
A hydrologic study involving the investigation of groundwater-surface water interactions along Ellerbe Creek, a major tributary to upper Falls Lake, was conducted in order to determine if groundwater is a likely source of nitrate input to the stream. Groundwater-surface water interactions were characterized by synoptic streamflow measurements, groundwater-level monitoring, hydrograph-separation methods and a continuous streambed temperature survey to aid in the collection and interpretation of water-quality samples along the stream.
The data set consists of marine seismic-reflection data that includes 34 SEGY data files, navigation data and a CSV format file with a list of files. The archived SEGY files, navigation files, and detailed metadata for these seismic reflections can also be downloaded from the National Archive of Marine Seismic Surveys (NAMSS). https://walrus.wr.usgs.gov/namss//survey/B-1-13-FL/ Marine seismic-reflection data were acquired in canals in eastern Broward County at two different times: February 2010 and April-June 2013, resulting in 34 SEGY data files.
Categories: Data;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Broward County,
Geophysics,
Miami-Dade County,
Seismology,
USA,
Earthquake instability occurs as a result of strength loss during sliding on a fault. It has been known for over 50 years that fault compaction or dilatancy may cause significant weakening or strengthening by dramatically changing the fluid pressure trapped in faults. Despite this fundamental importance, we have no real understanding of the exact conditions that lead to compaction or dilation during nucleation or rupture. To date, no direct measurements of pore pressure changes during slip in hydraulically isolated faults have been reported. We show direct examples of fluid pressure variations during nucleation and rupture using a miniature pressure transducer embedded in an experimental fault. We demonstrate that...
We present high-resolution (10-cm pixel) digital surface models (DSMs) generated for the northern 16 km of the surface rupture associated with the 1983 Mw 6.9 Borah Peak earthquake. These DSMs were generated using Agisoft Photoscan (and Metashape) image-based modeling software and low-altitude aerial photographs acquired from unmanned aircraft systems and a tethered balloon. DSM files consist of GeoTIFFs with georeferencing information stored in the file headers.
A database of geologic map of Three Sisters Volcanic Cluster as described in the original abstract: The geologic map represents part of a late Quaternary volcanic field within which scores of eruptions have taken place over the last 50,000 years, some as recently as ~1,500 years ago. No rocks of early Pleistocene (or greater) age crop out within the map area, although volcanic and derivative sedimentary rocks of Miocene and Pliocene age are widespread to the east and west and are certainly buried beneath the younger volcanic field. Of the 145 volcanic map units described herein, only 22 are certainly older than late Pleistocene (>126 ka), and 12 are postglacial (<15 ka). The oldest unit identified yields an age...
Categories: Data;
Types: ArcGIS REST Map Service,
ArcGIS Service Definition,
Downloadable,
Map Service;
Tags: Andesite,
Basalt,
Basaltic andesite,
Bend, Oregon,
Dacite,
The New Madrid Seismic Zone presents significant seismic hazard to the central and eastern United States. We mapped newly-identified coseismic ridge-spreading features, or sackungen, in the bluffs east of the Mississippi River in western Tennessee. We use this mapping dataset in an accompanying manuscript to show that sackungen form during earthquakes on the Reelfoot fault and may fail in preferred orientations. Ultimately, these data can be used to infer fault source and mechanism and improve the paleoseismic record used in hazard models.
This ScienceBase entry contains three seismic catalogs supporting and described by the manuscript - Koper, K. D., Pankow, K. L., Pechmann, J. C., Hale, J. M., Burlacu, R., Yeck, W. L., et al (2018). Afterslip Enhanced Aftershock Activity During the 2017 Earthquake Sequence Near Sulphur Peak, Idaho. Geophysical Research Letters, 45. https://doi.org/10.1029/2018GL078196. These are included in three separate catalog files: the University of Utah Seismograph Stations (UUSS) absolute locations, the MLOC relocations, and the GrowClust relocations. The absolute USGS locations are available from the USGS ComCat (https://earthquake.usgs.gov/data/comcat/).
A 3D temperature model is constructed in order to support the estimation of physical parameters within the USGS National Crustal Model. The crustal model is defined by a geological framework consisting of various lithologies with distinct mineral compositions. A temperature model is needed to calculate mineral density and bulk and shear modulus as a function of position within the crust. These properties control seismic velocity and impedance, which are needed to accurately estimate earthquake travel times and seismic amplitudes in earthquake hazard analyses. The temperature model is constrained by observations of surface temperature, temperature gradient, and conductivity, inferred Moho temperature and depth, and...
This data release contains model output from simulations presented in the associated Open-File Report (Barnhart and others, 2021). In this report, we present model results from four simulations (scenarios C-290, NC-290, C-689, NC-689, Table 1) of hypothetical rapid movement of landslides into adjacent fjord water at Barry Arm, Alaska using the D-Claw model (George and Iverson, 2014; Iverson and George, 2014). The basis for the four scenarios is described in Barnhart and others (2021). Table 1. Summary of four considered scenarios including key simulation input parameter values. Simulation input parameters Scenario name and description NC-290 C-290 NC-689 C-689 Symbol Units Description Smaller,...
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: Alaska,
Barry Arm,
D-Claw,
Geomorphology,
Geophysics,
CONTENTS OF THIS DATA RELEASE This data release contains supplementary material to the Geochistry, Geophysics, Geosystems article: "Modeling ash dispersal from future eruptions of Taupo supervolcano", by S.J. Barker et al. This paper uses Ash3d model simulations to calculate the probability of tephra inundation from eruptions of the following sizes: 0.1 km3, 1 km3, 5 km3, 50 km3, and 500 km3. All volume cases were modeled with umbrella cloud formation, with additional Ash3d simulations also run for the case of a 0.1 km3 eruption assuming no development of an umbrella cloud. One thousand model simulations were run for each of these cases. Other source parameters used for these simulations are described in the...
Success Dam spillway seismic refraction survey, Porterville, California, December 2018 and July 2019
Compressional- (P-) wave seismic refraction data were acquired in December 2018 and July 2019 along fourteen profiles within the spillway of Success Dam in Porterville, California. A new concrete ogee weir is planned for construction within the existing spillway, and the P-wave seismic velocity models will be used to inform further geotechnical investigations, including siting new geologic borings, and the advanced engineering design phases in terms of rock rippability and relative rock hardness/competency. Data acquisition, processing, and modeling were conducted collaboratively between the U.S. Geological Survey (USGS) and U.S. Army Corps of Engineers (USACE) Sacramento District. Data were acquired with Geometrics...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: California,
GGGSC,
Geology, Geophysics, and Geochemistry Science Center,
Geophysics,
Hydrology,
This publication provides digital flight line data for a high-resolution magnetic and radiometric survey over an area of northwest Arkansas. The airborne geophysical survey was jointly funded by the USGS National Cooperative Geologic Mapping Program and the Earth Mapping Resource Initiative and was designed to meet the complimentary needs related to geologic mapping and mineral resource research. The survey covers an irregular area 225 by 110 kilometer over the transition between the Ouachita and Ozarks Plateau physiographic provinces and includes 67,614 line-kilometers of magnetic and radiometric data. Data were collected from a fixed-wing aircraft flown at mean terrain clearance of 167 meters (m) above topography...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: AASG,
Association of American State Geologists,
Barry County,
Baxter County,
Boone County,
This data release provides digital flight line data for a high-resolution airborne magnetic and radiometric survey over Charleston, South Carolina and the surrounding region. These data were collected to better understand earthquake hazards in the Charleston seismic zone by imaging structural features in the crystalline basement and to image heavy mineral sands containing titanium, zirconium, and rare earth elements using radiometric data (gamma spectrometry), which is sensitive to thorium in monazite. This survey represents a collaborative effort by the U.S. Geological Survey (USGS) Earthquake Hazards Program, Mineral Resources Program, National Cooperative Mapping Program, and Earth Mapping Resource Initiative...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Berkeley County,
Charleston,
Charleston County,
Clarendon County,
Colleton County,
This dataset includes the magnetotelluric (MT) sounding data collected in 2005 along an east-west profile north of Wells, Nevada. It is important to know whether major mining districts in the Northern Nevada Gold Province are underlain by rocks of the Archean Wyoming craton, which are known to contain orogenic gold deposits, or by accreted rocks of the Paleoproterozoic Mojave province. It is also important to know the location and orientation of the Archean/Proterozoic suture zone between these provinces as well as major basement structures within these terranes because they may influence subsequent patterns of sedimentation, deformation, magmatism, and hydrothermal activity. This study was funded by the U.S. Geological...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Bishop Creek,
CGGSC,
Crustal Geophysics and Geochemistry Science Center,
Electromagnetic surveying,
Elko County,
This dataset includes magnetotelluric (MT) sounding data collected in July 2019 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 audiomagnetotellurics, the USGS collected MT data at 24 sites along five profiles ranging from 2 to 5 kilometers in length: across Red Mountain of the Silverton caldera, within the caldera in Eureka Graben, across the south-eastern margin of the caldera along Arrastra Gulch, across the southern margin of the caldera along the western margin of Kendall Mountain, and across the south-western margin of the caldera along South Fork...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Animas River,
Arrastra Gulch,
Colorado,
DOI,
Department of the Interior,
Note: There is an updated version of this data release, available here: https://doi.org/10.5066/P92R4OL2 A helicopter-borne electromagnetic/magnetic survey was flown over the Stillwater area, southwest Montana from May 5 to May 16, 2000. The survey was conducted over the Stillwater Igneous Complex, a Precambrian layered mafic-ultramafic intrusion which is characterized by igneous layering. Electromagnetic data were acquired using DIGHEM helicopter-borne electromagnetic system. Magnetic data were collected with optically pumped Cesium Vapor Geometrics G822 magnetometer. Sensor elevation above ground was measured with Honeywell/Sperry AA220 radar. The nominal elevation of the sensor was 60 meters. Survey coverage...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Geophysics,
Montana,
aeromagnetic surveying,
electromagnetic surveying,
geology,
The U.S. Geological Survey provides a wide range of scientific information to an even wider group of stakeholders. Understanding what capacities are needed and if and or where these capacities exist across the USGS landscape is critical in moving science to the next level of use, implementation, and visualization. The concept behind the groups organized to conduct and interpret the survey that collected these data took advantage of the USGS’s position as a science organization with expertise spanning a wide range of science disciplines, stakeholders, and responsibilities. A survey was conducted of USGS employees (Sep 20-Nov 20) to get a current sample of the capacities that exist across the USGS.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Aquatic Biology,
Botany,
Climatology,
Ecology,
Economic Geology,
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