Research Geophysicist
Geologic Hazards Science Center
Email:
olboyd@usgs.gov
Office Phone:
303-273-8617
Fax:
303-273-8452
ORCID:
0000-0001-9457-0407
Location
1711 Illinois St
P.O. Box 25046
Mail Stop 966
Denver
, CO
80225-0046
US
Supervisor:
Morgan P Moschetti
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This dataset of the elevation of basement and thickness of sediment above the syn- and post-rift unconformity (sediments above being generally Late Cretaceous and younger) was constructed for application to site response models in earthquake hazard analyses. Sediment thickness in meters is provided in zipped csv format on a 0.01-degree grid, and sediment thickness and basement elevation in meters relative to mean sea level are provided in GeoTIFF format on a 1-km grid.
Tags: EHP,
Earthquake Hazards Program,
GHSC,
Geologic Hazards Science Center,
Geophysics, All tags...
Seismology,
Structural Geology,
USGS,
USGS Science Data Catalog (SDC),
United States,
earthquake occurrences,
earthquakes,
geoscientificInformation,
hazards,
maps and atlases,
sediment thickness, Fewer tags
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A model of the lower seismogenic depth distribution of earthquakes in the western United States was developed to support models for seismic hazard assessment that will be included in the 2023 USGS National Seismic Hazard Model. This data release presents a recalibration using the hypocentral depths of events M>1 from the Advanced National Seismic System Comprehensive Earthquake Catalog from 1980 to 2021. For higher precision and better resolution in the model, the data were supplemented with seismicity from southern California that was relocated by Hauksson and others (2012). Along the San Andreas Fault, the deepest seismogenic depths are located at 23 km around the Cholame segment, whereas the shallowest depths...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Geophysics,
Seismology,
USGS Science Data Catalog (SDC),
United States,
earthquake occurrences, All tags...
earthquakes,
hazards,
seismology, Fewer tags
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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...
Tags: Earthquake Hazards Program,
GHSC,
Geologic Hazards Science Center,
Geophysics,
NCM, All tags...
Seismology,
Stratigraphy,
USGS,
USGS National Crustal Model,
USGS Science Data Catalog (SDC),
United States, Fewer tags
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The St. Louis area has experienced minor earthquake damage at least 12 times in the past 205 years. The St. Louis metropolitan area, with a population of about 2.8 million, faces earthquake hazard from large earthquakes in the New Madrid and Wabash Valley seismic zones, as well as a closer region of diffuse historical and prehistoric seismicity to its south and east. Also, low attenuation of seismic energy in the region and a substantial number of historic older unreinforced brick and stone buildings make the St. Louis area vulnerable to moderate earthquakes at relatively large distances compared to the western United States. This geotechnical database was compiled by James Palmer and others at the Missouri Department...
Tags: EHP,
Earthquake Hazards Program,
GHSC,
Geologic Hazards Science Center,
USGS, All tags...
USGS Science Data Catalog (SDC),
United States,
earthquake occurences,
earthquakes,
engineering geology,
geoscientificInformation,
hazards,
maps and atlases, Fewer tags
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We present a numeric grid containing estimates of the thickness of unconsolidated sediments for the western United States. Values for these grids were combined and integrated from previous studies or derived directly from gravity analyses. The grids are provided with 1-km grid-node spacing in WGS84 latitude-longitude coordinates. Detailed information regarding the derivation of these estimates is provided by Shah, A.K, and Boyd, O.S., 2018, Depth to basement and thickness of unconsolidated sediments for the western United States - Initial estimates for layers of the U.S. Geological Survey National Crustal Model: U.S. Geological Survey Open-File Report 2018-1115, https://doi.org/10.3133/ofr20181115.
Categories: Data;
Tags: Arizona,
CGGSC,
California,
Colorado,
GHSC, All tags...
Geologic Hazards Science Center,
Geology, Geophysics, and Geochemistry Science Center,
Idaho,
Kansas,
Montana,
National Crustal Model,
Nebraska (west),
Nevada,
New Mexico,
North Dakota (west),
Oklahoma (panhandle),
Oregon,
South Dakota (west),
Texas (west),
USGS Science Data Catalog (SDC),
Washington,
Western United States,
Wyoming,
basins,
earthquake response,
earthquakes,
geoscientificInformation,
gravity,
hazards,
regional study,
sediments,
three-dimensional mapping,
unconsolidated sediments, Fewer tags
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