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Victoria Langenheim

Vickie is a Research Geophysicist with the Geology, Minerals, Energy, and Geophysics Science Center

Science and Products

San Andreas Fault in the Carrizo Plain

San Andreas Fault System in Southern California

Southern California is home to nearly 24 million people and countless visitors who live, recreate, consume resources, and face the risk of natural hazards in the region. This project produces high-quality, multi-purpose geologic maps, databases, and reports that portray our understanding of the region’s four-dimensional geologic framework. We conduct stratigraphic, structural, geomorphological...
By
Core Science Systems Mission Area, Geology, Minerals, Energy, and Geophysics Science Center
San Andreas Fault System in Southern California

San Andreas Fault System in Southern California

Southern California is home to nearly 24 million people and countless visitors who live, recreate, consume resources, and face the risk of natural hazards in the region. This project produces high-quality, multi-purpose geologic maps, databases, and reports that portray our understanding of the region’s four-dimensional geologic framework. We conduct stratigraphic, structural, geomorphological...
Learn More
3-D Geologic Map

2D and 3D Geologic Mapping and Earthquake Hazards of California

This project uses geologic and geophysical mapping to build an earth-science framework for scientific investigations that include assessments of critical resources, such as groundwater, and of hazards, such as those resulting from earthquakes, in California west of and including the Sierra Nevada and Cascade arc. Questions of particular interest include: What are the geometries, slip rates, and...
By
National Cooperative Geologic Mapping Program, California Water Science Center, Geology, Minerals, Energy, and Geophysics Science Center
2D and 3D Geologic Mapping and Earthquake Hazards of California

2D and 3D Geologic Mapping and Earthquake Hazards of California

This project uses geologic and geophysical mapping to build an earth-science framework for scientific investigations that include assessments of critical resources, such as groundwater, and of hazards, such as those resulting from earthquakes, in California west of and including the Sierra Nevada and Cascade arc. Questions of particular interest include: What are the geometries, slip rates, and...
Learn More
Filter Total Items: 36

Seismic-reflection profiles in Chuckwalla Valley, southeastern California Seismic-reflection profiles in Chuckwalla Valley, southeastern California

Two industry seismic-reflection profiles in Chuckwalla Valley (southeastern California) were donated by Buckhorn Petroleum to the CALCRUST program in ~1987. USGS personnel Jeff Wilson, Eric Geist, and Jill McCarthy reprocessed the seismic reflection data, concentrating on imaging reflections below the Cenozoic basin fill using pre-stack techniques. This data release describes the...
By
Geology, Minerals, Energy, and Geophysics Science Center

Geophysical grids, horizontal gradient maxima and depth to bedrock of the Blythe region, California and Arizona Geophysical grids, horizontal gradient maxima and depth to bedrock of the Blythe region, California and Arizona

This data release contains (1) geophysical grids, (2) horizontal gravity and residual magnetic gradient maxima and (3) inputs to a gravity inversion of Cenozoic basin thickness based on gravity measurements of the Blythe region of California and Arizona. Gridded data (geotiffs.zip) consist of the input isostatic gravity grid as well as grids of Cenozoic basin thickness and bedrock...
By
Geology, Minerals, Energy, and Geophysics Science Center

Gravity and physical property data of northeastern California (ver. 2.0, December 2025) Gravity and physical property data of northeastern California (ver. 2.0, December 2025)

This data release contains principal facts of gravity measurements by previous studies and collected by the U.S. Geological Survey in 1994-2023 and a compilation of existing and new density and magnetic susceptibility data in northeastern California. Gravity data are processed to isostatic anomalies using reduction densities of 2670 and 2200 kilogram/cubic meter. This region is at the...
By
Geology, Energy, and Minerals Mission Area, Geology, Minerals, Energy, and Geophysics Science Center

Gravity data and basin thickness grids for "Geophysical evidence for wedging in the San Gorgonio Pass structural knot, southern San Andreas fault zone, southern California" Gravity data and basin thickness grids for "Geophysical evidence for wedging in the San Gorgonio Pass structural knot, southern San Andreas fault zone, southern California"

This data release contains (1) principal facts of gravity measurements collected by the U.S. Geological Survey in 2000-2004 (usgs_iso.csv) and (2) inputs to a gravity inversion of Cenozoic basin thickness based on those gravity and previous measurements. Gridded data (geotiffs.zip) consist of the input isostatic gravity grid as well as grids of Cenozoic basin thickness and basement...
By
Geology, Minerals, Energy, and Geophysics Science Center

Gravity data, geophysical grids, and horizontal gradient maxima of the Healdsburg 30 by 60 minute quadrangle, California Gravity data, geophysical grids, and horizontal gradient maxima of the Healdsburg 30 by 60 minute quadrangle, California

This data release contains (1) principal facts of gravity measurements by previous studies and collected by the U.S. Geological Survey in 2006-2024, (2) geophysical grids, and (3) horizontal gradient maxima derived from gravity and magnetic potential fields of the Healdsburg 30 by 60 minute quadrangle, California. Gridded data are provided in geotiff format. These data support modeling...
By
Geology, Minerals, Energy, and Geophysics Science Center

Gravity and physical property data of the 2019 Ridgecrest earthquakes region, Mojave Desert, California Gravity and physical property data of the 2019 Ridgecrest earthquakes region, Mojave Desert, California

This data release presents point data associated with studies to understand the crustal structure of the 2019 Ridgecrest earthquakes epicentral region and the interaction of the northeast-to-east-striking Garlock fault with the northwest-striking faults of the Eastern California Shear Zone and Walker Lane. Data include principal fact information for new gravity measurements collected by...
By
Natural Hazards Mission Area, National Cooperative Geologic Mapping Program, Geology, Minerals, Energy, and Geophysics Science Center

Preliminary Digital Database for the Portola 30' x 60' Geologic and Geophysical Map, California Preliminary Digital Database for the Portola 30' x 60' Geologic and Geophysical Map, California

This geospatial dataset compiles, in digital form, geologic and geophysical data for the Portola 30’x 60’ quadrangle, located in the northern Sierra Nevada, California. This geologic map of the Portola 30’x 60’ quadrangle integrates decades of published and unpublished mapping in the northern Sierra Nevada. In conjunction with geophysical data, including more than 1000 new gravity...
By
National Cooperative Geologic Mapping Program

Gravity and physical property data of the Blythe region, California and Arizona Gravity and physical property data of the Blythe region, California and Arizona

This data release presents point data associated with studies to understand the crustal structure of the Blythe region, where strands of the pre-Quaternary Eastern California Shear zone project across this region in California and Arizona. Data include principal fact information for new gravity measurements collected by the U.S. Geological Survey from 2020 to 2025, previously unpublished...
By
National Cooperative Geologic Mapping Program, Geology, Minerals, Energy, and Geophysics Science Center

Tabular uranium-lead and trace-element compositional data of zircons and whole-rock geochemistry of plutonic rocks in the Sierra Nevada, California Tabular uranium-lead and trace-element compositional data of zircons and whole-rock geochemistry of plutonic rocks in the Sierra Nevada, California

This dataset consists of zircon uranium-lead (U-Pb) isotopic compositions, ages, and trace-element compositions in addition to whole-rock chemical compositions from plutons within the Sierra Nevada, California. These samples primarily collected from 2015 to 2023, although some legacy data are included. Zircon crystals were analyzed using the Sensitive High-Resolution Ion Micro-Probe...
By
Geology, Minerals, Energy, and Geophysics Science Center

P- and S-Wave Suspension Velocity Logs in the San Francisco Bay Region, Alameda, Santa Clara, and Sonoma Counties, California P- and S-Wave Suspension Velocity Logs in the San Francisco Bay Region, Alameda, Santa Clara, and Sonoma Counties, California

This data release contains P- and S-wave velocity data from logs of nine wells in three large sedimentary basins in the San Francisco Bay region. The logs were collected between 2000 and 2006 for the U.S. Geological Survey under contract by R.A. Steller of GeoVision using an Oyo suspension logging system. Well depths range from 215 to 407 meters and sample spacing in the wells ranges...
By
Geology, Minerals, Energy, and Geophysics Science Center

Digitized sonic velocity and density log data of the Eel River area, northern California Digitized sonic velocity and density log data of the Eel River area, northern California

Sonic velocity and density well logs in the Eel River area in northern California (Ferndale north Arcata) were digitized by hand. These logs are available as scanned files (pdfs and tiffs) on the California Division of Oil, Gas, and Geothermal Resources website (https://maps.conservation.ca.gov/doggr/wellfinder/). The data consist of transit times and bulk density measured downhole in...
By
Geology, Minerals, Energy, and Geophysics Science Center

Geophysical data and grids of the Grouse Creek and Utah part of the Jackpot 30' x 60' quadrangles, Utah Geophysical data and grids of the Grouse Creek and Utah part of the Jackpot 30' x 60' quadrangles, Utah

New geophysical data, including density and magnetic susceptibility measurements, were collected in the Grouse Creek and Utah part of the Jackpot 30' x 60' quadrangles in Box Elder County, Utah and Cassia County, Idaho. The release contains 324 new gravity measurements merged with a 2013 compilation. These data were inverted for basin thickness and basement density variations. The...
By
Geology, Minerals, Energy, and Geophysics Science Center
No results found.
Filter Total Items: 191

Preliminary report on geophysical data in Yavapai County, Arizona Preliminary report on geophysical data in Yavapai County, Arizona

Recently acquired geophysical data provide information on the geologic framework and its effect of groundwater flow and on stream/aquifer interaction in Yavapai County, Arizona. High-resolution aeromagnetic data reflect diverse rock types at and below the topographic surface and have permitted a preliminary interpretation of faults and underlying rock types (in particular, volcanic) that...
Authors
V.E. Langenheim, J.P. Hoffmann, K.W. Blasch, Ed DeWitt, Laurie Wirt
By
Geology, Energy, and Minerals Mission Area, Energy Resources Program, Mineral Resources Program, Science and Decisions Center, Groundwater and Streamflow Information Program, Geology, Minerals, Energy, and Geophysics Science Center

Aeromagnetic Expression of Buried Basaltic Volcanoes Near Yucca Mountain, Nevada Aeromagnetic Expression of Buried Basaltic Volcanoes Near Yucca Mountain, Nevada

A high-resolution aeromagnetic survey has defined a number of small dipolar anomalies indicating the presence of magnetic bodies buried beneath the surface of Crater Flat and the Amargosa Desert. Results of potential-field modeling indicate that isolated, small-volume, highly magnetic bodies embedded within the alluvial deposits of both areas produce the anomalies. Their physical...
Authors
Dennis W. O’Leary, E. A. Mankinen, R.J. Blakely, V.E. Langenheim, D. A. Ponce
By
Geology, Minerals, Energy, and Geophysics Science Center, Geology, Geophysics, and Geochemistry Science Center

Relationship of the 1999 Hector Mine and 1992 Landers fault ruptures to offsets on neogene faults and distribution of late Cenozoic basins in the eastern California shear zone Relationship of the 1999 Hector Mine and 1992 Landers fault ruptures to offsets on neogene faults and distribution of late Cenozoic basins in the eastern California shear zone

This report examines the Hector Mine and Landers earthquakes in the broader context of faults and fault-related basins of the eastern California shear zone (ECSZ). We compile new estimates of total strike-slip offset (horizontal separation) at nearly 30 fault sites based on offset magnetic anomaly pairs. We also present a map of the depth to pre-Cenozoic basement rock (thickness of basin...
Authors
R.C. Jachens, V.E. Langenheim, J. C. Matti

The Emerson Lake Body: A link between the Landers and Hector Mine earthquakes, southern California, as inferred from gravity and magnetic anomalies The Emerson Lake Body: A link between the Landers and Hector Mine earthquakes, southern California, as inferred from gravity and magnetic anomalies

Gravity and magnetic data indicate a mafic crustal heterogeneity that lies between the Hector Mine 16 October 1999 (Mw 7.1) and Landers 28 June 1992 (Mw 7.3) epicenters. The aftershocks and ruptures of these two events avoided the interior of the body. Two- and three-dimensional modeling of the potential-field anomalies shows that the source, here named the Emerson Lake body (ELB)...
Authors
V.E. Langenheim, R.C. Jachens
By
Geology, Minerals, Energy, and Geophysics Science Center

Lower crustal deformation beneath the central Transverse Ranges, southern California: Results from the Los Angeles Region Seismic Experiment Lower crustal deformation beneath the central Transverse Ranges, southern California: Results from the Los Angeles Region Seismic Experiment

We present a P wave velocity model derived from active source seismic data collected during the 1994 Los Angeles Region Seismic Experiment. Our model extends previously published upper crustal velocity models to mantle depths. Our model was developed by both ray tracing through a layered model and calculating travel times through a gridded model. It includes an 8-km-thick crustal root...
Authors
N. J. Godfrey, Gary S. Fuis, Victoria E. Langenheim, David A. Okaya, Thomas M. Brocher
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center, Geology, Minerals, Energy, and Geophysics Science Center

Gravity data along LARSE (Los Angeles Regional Seismic Experiment) Line II, southern California Gravity data along LARSE (Los Angeles Regional Seismic Experiment) Line II, southern California

The U.S. Geological Survey conducted a detailed gravity study along part of the Los Angeles Regional Seismic Experiment (LARSE) transect across the San Fernando Basin and Transverse Ranges to help characterize the structure underlying this area. 249 gravity measurements were collected along the transect and to augment regional coverage near the profile. An isostatic gravity low of 50-60...
Authors
R .J. Wooley, V.E. Langenheim
By
Geology, Energy, and Minerals Mission Area, Energy Resources Program, Mineral Resources Program, Science and Decisions Center, Groundwater and Streamflow Information Program, Geology, Minerals, Energy, and Geophysics Science Center

Upper crustal structure in Puget Lowland, Washington: Results from the 1998 Seismic Hazards Investigation in Puget Sound Upper crustal structure in Puget Lowland, Washington: Results from the 1998 Seismic Hazards Investigation in Puget Sound

A new three-dimensional (3-D) model shows seismic velocities beneath the Puget Lowland to a depth of 11 km. The model is based on a tomographic inversion of nearly one million first-arrival travel times recorded during the 1998 Seismic Hazards Investigation in Puget Sound (SHIPS), allowing higher-resolution mapping of subsurface structures than previously possible. The model allows us to...
Authors
T.M. Brocher, T. Parsons, R.J. Blakely, N.I. Christensen, M. A. Fisher, R.E. Wells, Uri S. ten Brink, T. L. Pratt, R. S. Crosson, K. C. Creager, N. P. Symons, L.A. Preston, T. Van Wagoner, K.C. Miller, C.M. Snelson, A.M. Trehu, V.E. Langenheim, G.D. Spence, K. Ramachandran, R.A. Hyndman, D. C. Mosher, B.C. Zelt, C.S. Weaver

Thickness and geometry of Cenozoic deposits in California Wash area, Nevada, based on gravity and seismic-reflection data Thickness and geometry of Cenozoic deposits in California Wash area, Nevada, based on gravity and seismic-reflection data

Gravity and seismic-reflection data provide insights into the subsurface stratigraphy and structure of the California Wash area of southern Nevada. This area is part of the Lower Colorado flow system and stratigraphic and structural data are important inputs into developing the hydrogeologic framework. These data indicate that the basin beneath California Wash reaches depths of 2-3 km...
Authors
V.E. Langenheim, J. J. Miller, W. R. Page, J. A. Grow

Comparision between crustal density and velocity variations in Southern California Comparision between crustal density and velocity variations in Southern California

We predict gravity from a three-dimensional Vp model of the upper crust and compare it to the observed isostatic residual gravity field. In general this comparison shows that the isostatic residual gravity field reflects the density variations in the upper to middle crust. Both data sets show similar density variations for the upper crust in areas such as the Peninsular Ranges and the...
Authors
V.E. Langenheim, E. Hauksson

Geophysical constraints on the location and geometry of the Las Vegas Shear Zone, Nevada Geophysical constraints on the location and geometry of the Las Vegas Shear Zone, Nevada

We model the basin configuration beneath Las Vegas Valley, Nevada, on the basis of gravity, drillhole, and seismic reflection data. We locate and characterize the various strands of the Las Vegas Valley Shear Zone (LVVSZ) by variations in basin thickness beneath the valley. The pre-Tertiary bedrock surface is complex, with subbasins buried beneath the flat alluvial surface of the valley...
Authors
V.E. Langenheim, J. A. Grow, R.C. Jachens, G. L. Dixon, J. J. Miller

Implications for the formation of the Hollywood Basin from gravity interpretations of the northern Los Angeles Basin, California Implications for the formation of the Hollywood Basin from gravity interpretations of the northern Los Angeles Basin, California

Gravity data provide insights on the complex tectonic history and structural development of the northern Los Angeles Basin region. The Hollywood basin appears to be a long (> 12 km), narrow (up to 2 km wide) trough lying between the Santa Monica Mountains and the Wilshire arch. In the deepest parts of the Hollywood basin, the modeled average thickness ranges from roughly 250 m if filled...
Authors
Thomas G. Hildenbrand, Jeffrey G. Davidson, Daniel J. Ponti, V.E. Langenheim
By
Natural Hazards Mission Area, Geology, Energy, and Minerals Mission Area, Earthquake Hazards Program, Energy Resources Program, Mineral Resources Program, Science and Decisions Center, Groundwater and Streamflow Information Program, Earthquake Science Center, Geology, Minerals, Energy, and Geophysics Science Center

Preliminary potential-field constraints on the geometry of the San Fernando basin, Southern California Preliminary potential-field constraints on the geometry of the San Fernando basin, Southern California

Gravity and magnetic data provide new insights on the structural underpinnings of the San Fernando Basin region, which may be important to ground motion models. Gravity data indicate that a deep basin (>5 km) underlies the northern part of the San Fernando Valley; this deep basin is required to explain the lowest gravity values over the Mission Hills thrust fault. Gravity modeling...
Authors
Victoria E. Langenheim, Andrew Griscom, R.C. Jachens, T.G. Hildenbrand
By
Geology, Energy, and Minerals Mission Area, Energy Resources Program, Mineral Resources Program, Science and Decisions Center, Groundwater and Streamflow Information Program, Geology, Minerals, Energy, and Geophysics Science Center

Science and Products

San Andreas Fault in the Carrizo Plain

San Andreas Fault System in Southern California

Southern California is home to nearly 24 million people and countless visitors who live, recreate, consume resources, and face the risk of natural hazards in the region. This project produces high-quality, multi-purpose geologic maps, databases, and reports that portray our understanding of the region’s four-dimensional geologic framework. We conduct stratigraphic, structural, geomorphological...
By
Core Science Systems Mission Area, Geology, Minerals, Energy, and Geophysics Science Center
San Andreas Fault System in Southern California

San Andreas Fault System in Southern California

Southern California is home to nearly 24 million people and countless visitors who live, recreate, consume resources, and face the risk of natural hazards in the region. This project produces high-quality, multi-purpose geologic maps, databases, and reports that portray our understanding of the region’s four-dimensional geologic framework. We conduct stratigraphic, structural, geomorphological...
Learn More
3-D Geologic Map

2D and 3D Geologic Mapping and Earthquake Hazards of California

This project uses geologic and geophysical mapping to build an earth-science framework for scientific investigations that include assessments of critical resources, such as groundwater, and of hazards, such as those resulting from earthquakes, in California west of and including the Sierra Nevada and Cascade arc. Questions of particular interest include: What are the geometries, slip rates, and...
By
National Cooperative Geologic Mapping Program, California Water Science Center, Geology, Minerals, Energy, and Geophysics Science Center
2D and 3D Geologic Mapping and Earthquake Hazards of California

2D and 3D Geologic Mapping and Earthquake Hazards of California

This project uses geologic and geophysical mapping to build an earth-science framework for scientific investigations that include assessments of critical resources, such as groundwater, and of hazards, such as those resulting from earthquakes, in California west of and including the Sierra Nevada and Cascade arc. Questions of particular interest include: What are the geometries, slip rates, and...
Learn More
Filter Total Items: 36

Seismic-reflection profiles in Chuckwalla Valley, southeastern California Seismic-reflection profiles in Chuckwalla Valley, southeastern California

Two industry seismic-reflection profiles in Chuckwalla Valley (southeastern California) were donated by Buckhorn Petroleum to the CALCRUST program in ~1987. USGS personnel Jeff Wilson, Eric Geist, and Jill McCarthy reprocessed the seismic reflection data, concentrating on imaging reflections below the Cenozoic basin fill using pre-stack techniques. This data release describes the...
By
Geology, Minerals, Energy, and Geophysics Science Center

Geophysical grids, horizontal gradient maxima and depth to bedrock of the Blythe region, California and Arizona Geophysical grids, horizontal gradient maxima and depth to bedrock of the Blythe region, California and Arizona

This data release contains (1) geophysical grids, (2) horizontal gravity and residual magnetic gradient maxima and (3) inputs to a gravity inversion of Cenozoic basin thickness based on gravity measurements of the Blythe region of California and Arizona. Gridded data (geotiffs.zip) consist of the input isostatic gravity grid as well as grids of Cenozoic basin thickness and bedrock...
By
Geology, Minerals, Energy, and Geophysics Science Center

Gravity and physical property data of northeastern California (ver. 2.0, December 2025) Gravity and physical property data of northeastern California (ver. 2.0, December 2025)

This data release contains principal facts of gravity measurements by previous studies and collected by the U.S. Geological Survey in 1994-2023 and a compilation of existing and new density and magnetic susceptibility data in northeastern California. Gravity data are processed to isostatic anomalies using reduction densities of 2670 and 2200 kilogram/cubic meter. This region is at the...
By
Geology, Energy, and Minerals Mission Area, Geology, Minerals, Energy, and Geophysics Science Center

Gravity data and basin thickness grids for "Geophysical evidence for wedging in the San Gorgonio Pass structural knot, southern San Andreas fault zone, southern California" Gravity data and basin thickness grids for "Geophysical evidence for wedging in the San Gorgonio Pass structural knot, southern San Andreas fault zone, southern California"

This data release contains (1) principal facts of gravity measurements collected by the U.S. Geological Survey in 2000-2004 (usgs_iso.csv) and (2) inputs to a gravity inversion of Cenozoic basin thickness based on those gravity and previous measurements. Gridded data (geotiffs.zip) consist of the input isostatic gravity grid as well as grids of Cenozoic basin thickness and basement...
By
Geology, Minerals, Energy, and Geophysics Science Center

Gravity data, geophysical grids, and horizontal gradient maxima of the Healdsburg 30 by 60 minute quadrangle, California Gravity data, geophysical grids, and horizontal gradient maxima of the Healdsburg 30 by 60 minute quadrangle, California

This data release contains (1) principal facts of gravity measurements by previous studies and collected by the U.S. Geological Survey in 2006-2024, (2) geophysical grids, and (3) horizontal gradient maxima derived from gravity and magnetic potential fields of the Healdsburg 30 by 60 minute quadrangle, California. Gridded data are provided in geotiff format. These data support modeling...
By
Geology, Minerals, Energy, and Geophysics Science Center

Gravity and physical property data of the 2019 Ridgecrest earthquakes region, Mojave Desert, California Gravity and physical property data of the 2019 Ridgecrest earthquakes region, Mojave Desert, California

This data release presents point data associated with studies to understand the crustal structure of the 2019 Ridgecrest earthquakes epicentral region and the interaction of the northeast-to-east-striking Garlock fault with the northwest-striking faults of the Eastern California Shear Zone and Walker Lane. Data include principal fact information for new gravity measurements collected by...
By
Natural Hazards Mission Area, National Cooperative Geologic Mapping Program, Geology, Minerals, Energy, and Geophysics Science Center

Preliminary Digital Database for the Portola 30' x 60' Geologic and Geophysical Map, California Preliminary Digital Database for the Portola 30' x 60' Geologic and Geophysical Map, California

This geospatial dataset compiles, in digital form, geologic and geophysical data for the Portola 30’x 60’ quadrangle, located in the northern Sierra Nevada, California. This geologic map of the Portola 30’x 60’ quadrangle integrates decades of published and unpublished mapping in the northern Sierra Nevada. In conjunction with geophysical data, including more than 1000 new gravity...
By
National Cooperative Geologic Mapping Program

Gravity and physical property data of the Blythe region, California and Arizona Gravity and physical property data of the Blythe region, California and Arizona

This data release presents point data associated with studies to understand the crustal structure of the Blythe region, where strands of the pre-Quaternary Eastern California Shear zone project across this region in California and Arizona. Data include principal fact information for new gravity measurements collected by the U.S. Geological Survey from 2020 to 2025, previously unpublished...
By
National Cooperative Geologic Mapping Program, Geology, Minerals, Energy, and Geophysics Science Center

Tabular uranium-lead and trace-element compositional data of zircons and whole-rock geochemistry of plutonic rocks in the Sierra Nevada, California Tabular uranium-lead and trace-element compositional data of zircons and whole-rock geochemistry of plutonic rocks in the Sierra Nevada, California

This dataset consists of zircon uranium-lead (U-Pb) isotopic compositions, ages, and trace-element compositions in addition to whole-rock chemical compositions from plutons within the Sierra Nevada, California. These samples primarily collected from 2015 to 2023, although some legacy data are included. Zircon crystals were analyzed using the Sensitive High-Resolution Ion Micro-Probe...
By
Geology, Minerals, Energy, and Geophysics Science Center

P- and S-Wave Suspension Velocity Logs in the San Francisco Bay Region, Alameda, Santa Clara, and Sonoma Counties, California P- and S-Wave Suspension Velocity Logs in the San Francisco Bay Region, Alameda, Santa Clara, and Sonoma Counties, California

This data release contains P- and S-wave velocity data from logs of nine wells in three large sedimentary basins in the San Francisco Bay region. The logs were collected between 2000 and 2006 for the U.S. Geological Survey under contract by R.A. Steller of GeoVision using an Oyo suspension logging system. Well depths range from 215 to 407 meters and sample spacing in the wells ranges...
By
Geology, Minerals, Energy, and Geophysics Science Center

Digitized sonic velocity and density log data of the Eel River area, northern California Digitized sonic velocity and density log data of the Eel River area, northern California

Sonic velocity and density well logs in the Eel River area in northern California (Ferndale north Arcata) were digitized by hand. These logs are available as scanned files (pdfs and tiffs) on the California Division of Oil, Gas, and Geothermal Resources website (https://maps.conservation.ca.gov/doggr/wellfinder/). The data consist of transit times and bulk density measured downhole in...
By
Geology, Minerals, Energy, and Geophysics Science Center

Geophysical data and grids of the Grouse Creek and Utah part of the Jackpot 30' x 60' quadrangles, Utah Geophysical data and grids of the Grouse Creek and Utah part of the Jackpot 30' x 60' quadrangles, Utah

New geophysical data, including density and magnetic susceptibility measurements, were collected in the Grouse Creek and Utah part of the Jackpot 30' x 60' quadrangles in Box Elder County, Utah and Cassia County, Idaho. The release contains 324 new gravity measurements merged with a 2013 compilation. These data were inverted for basin thickness and basement density variations. The...
By
Geology, Minerals, Energy, and Geophysics Science Center
No results found.
Filter Total Items: 191

Preliminary report on geophysical data in Yavapai County, Arizona Preliminary report on geophysical data in Yavapai County, Arizona

Recently acquired geophysical data provide information on the geologic framework and its effect of groundwater flow and on stream/aquifer interaction in Yavapai County, Arizona. High-resolution aeromagnetic data reflect diverse rock types at and below the topographic surface and have permitted a preliminary interpretation of faults and underlying rock types (in particular, volcanic) that...
Authors
V.E. Langenheim, J.P. Hoffmann, K.W. Blasch, Ed DeWitt, Laurie Wirt
By
Geology, Energy, and Minerals Mission Area, Energy Resources Program, Mineral Resources Program, Science and Decisions Center, Groundwater and Streamflow Information Program, Geology, Minerals, Energy, and Geophysics Science Center

Aeromagnetic Expression of Buried Basaltic Volcanoes Near Yucca Mountain, Nevada Aeromagnetic Expression of Buried Basaltic Volcanoes Near Yucca Mountain, Nevada

A high-resolution aeromagnetic survey has defined a number of small dipolar anomalies indicating the presence of magnetic bodies buried beneath the surface of Crater Flat and the Amargosa Desert. Results of potential-field modeling indicate that isolated, small-volume, highly magnetic bodies embedded within the alluvial deposits of both areas produce the anomalies. Their physical...
Authors
Dennis W. O’Leary, E. A. Mankinen, R.J. Blakely, V.E. Langenheim, D. A. Ponce
By
Geology, Minerals, Energy, and Geophysics Science Center, Geology, Geophysics, and Geochemistry Science Center

Relationship of the 1999 Hector Mine and 1992 Landers fault ruptures to offsets on neogene faults and distribution of late Cenozoic basins in the eastern California shear zone Relationship of the 1999 Hector Mine and 1992 Landers fault ruptures to offsets on neogene faults and distribution of late Cenozoic basins in the eastern California shear zone

This report examines the Hector Mine and Landers earthquakes in the broader context of faults and fault-related basins of the eastern California shear zone (ECSZ). We compile new estimates of total strike-slip offset (horizontal separation) at nearly 30 fault sites based on offset magnetic anomaly pairs. We also present a map of the depth to pre-Cenozoic basement rock (thickness of basin...
Authors
R.C. Jachens, V.E. Langenheim, J. C. Matti

The Emerson Lake Body: A link between the Landers and Hector Mine earthquakes, southern California, as inferred from gravity and magnetic anomalies The Emerson Lake Body: A link between the Landers and Hector Mine earthquakes, southern California, as inferred from gravity and magnetic anomalies

Gravity and magnetic data indicate a mafic crustal heterogeneity that lies between the Hector Mine 16 October 1999 (Mw 7.1) and Landers 28 June 1992 (Mw 7.3) epicenters. The aftershocks and ruptures of these two events avoided the interior of the body. Two- and three-dimensional modeling of the potential-field anomalies shows that the source, here named the Emerson Lake body (ELB)...
Authors
V.E. Langenheim, R.C. Jachens
By
Geology, Minerals, Energy, and Geophysics Science Center

Lower crustal deformation beneath the central Transverse Ranges, southern California: Results from the Los Angeles Region Seismic Experiment Lower crustal deformation beneath the central Transverse Ranges, southern California: Results from the Los Angeles Region Seismic Experiment

We present a P wave velocity model derived from active source seismic data collected during the 1994 Los Angeles Region Seismic Experiment. Our model extends previously published upper crustal velocity models to mantle depths. Our model was developed by both ray tracing through a layered model and calculating travel times through a gridded model. It includes an 8-km-thick crustal root...
Authors
N. J. Godfrey, Gary S. Fuis, Victoria E. Langenheim, David A. Okaya, Thomas M. Brocher
By
Natural Hazards Mission Area, Earthquake Hazards Program, Earthquake Science Center, Geology, Minerals, Energy, and Geophysics Science Center

Gravity data along LARSE (Los Angeles Regional Seismic Experiment) Line II, southern California Gravity data along LARSE (Los Angeles Regional Seismic Experiment) Line II, southern California

The U.S. Geological Survey conducted a detailed gravity study along part of the Los Angeles Regional Seismic Experiment (LARSE) transect across the San Fernando Basin and Transverse Ranges to help characterize the structure underlying this area. 249 gravity measurements were collected along the transect and to augment regional coverage near the profile. An isostatic gravity low of 50-60...
Authors
R .J. Wooley, V.E. Langenheim
By
Geology, Energy, and Minerals Mission Area, Energy Resources Program, Mineral Resources Program, Science and Decisions Center, Groundwater and Streamflow Information Program, Geology, Minerals, Energy, and Geophysics Science Center

Upper crustal structure in Puget Lowland, Washington: Results from the 1998 Seismic Hazards Investigation in Puget Sound Upper crustal structure in Puget Lowland, Washington: Results from the 1998 Seismic Hazards Investigation in Puget Sound

A new three-dimensional (3-D) model shows seismic velocities beneath the Puget Lowland to a depth of 11 km. The model is based on a tomographic inversion of nearly one million first-arrival travel times recorded during the 1998 Seismic Hazards Investigation in Puget Sound (SHIPS), allowing higher-resolution mapping of subsurface structures than previously possible. The model allows us to...
Authors
T.M. Brocher, T. Parsons, R.J. Blakely, N.I. Christensen, M. A. Fisher, R.E. Wells, Uri S. ten Brink, T. L. Pratt, R. S. Crosson, K. C. Creager, N. P. Symons, L.A. Preston, T. Van Wagoner, K.C. Miller, C.M. Snelson, A.M. Trehu, V.E. Langenheim, G.D. Spence, K. Ramachandran, R.A. Hyndman, D. C. Mosher, B.C. Zelt, C.S. Weaver

Thickness and geometry of Cenozoic deposits in California Wash area, Nevada, based on gravity and seismic-reflection data Thickness and geometry of Cenozoic deposits in California Wash area, Nevada, based on gravity and seismic-reflection data

Gravity and seismic-reflection data provide insights into the subsurface stratigraphy and structure of the California Wash area of southern Nevada. This area is part of the Lower Colorado flow system and stratigraphic and structural data are important inputs into developing the hydrogeologic framework. These data indicate that the basin beneath California Wash reaches depths of 2-3 km...
Authors
V.E. Langenheim, J. J. Miller, W. R. Page, J. A. Grow

Comparision between crustal density and velocity variations in Southern California Comparision between crustal density and velocity variations in Southern California

We predict gravity from a three-dimensional Vp model of the upper crust and compare it to the observed isostatic residual gravity field. In general this comparison shows that the isostatic residual gravity field reflects the density variations in the upper to middle crust. Both data sets show similar density variations for the upper crust in areas such as the Peninsular Ranges and the...
Authors
V.E. Langenheim, E. Hauksson

Geophysical constraints on the location and geometry of the Las Vegas Shear Zone, Nevada Geophysical constraints on the location and geometry of the Las Vegas Shear Zone, Nevada

We model the basin configuration beneath Las Vegas Valley, Nevada, on the basis of gravity, drillhole, and seismic reflection data. We locate and characterize the various strands of the Las Vegas Valley Shear Zone (LVVSZ) by variations in basin thickness beneath the valley. The pre-Tertiary bedrock surface is complex, with subbasins buried beneath the flat alluvial surface of the valley...
Authors
V.E. Langenheim, J. A. Grow, R.C. Jachens, G. L. Dixon, J. J. Miller

Implications for the formation of the Hollywood Basin from gravity interpretations of the northern Los Angeles Basin, California Implications for the formation of the Hollywood Basin from gravity interpretations of the northern Los Angeles Basin, California

Gravity data provide insights on the complex tectonic history and structural development of the northern Los Angeles Basin region. The Hollywood basin appears to be a long (> 12 km), narrow (up to 2 km wide) trough lying between the Santa Monica Mountains and the Wilshire arch. In the deepest parts of the Hollywood basin, the modeled average thickness ranges from roughly 250 m if filled...
Authors
Thomas G. Hildenbrand, Jeffrey G. Davidson, Daniel J. Ponti, V.E. Langenheim
By
Natural Hazards Mission Area, Geology, Energy, and Minerals Mission Area, Earthquake Hazards Program, Energy Resources Program, Mineral Resources Program, Science and Decisions Center, Groundwater and Streamflow Information Program, Earthquake Science Center, Geology, Minerals, Energy, and Geophysics Science Center

Preliminary potential-field constraints on the geometry of the San Fernando basin, Southern California Preliminary potential-field constraints on the geometry of the San Fernando basin, Southern California

Gravity and magnetic data provide new insights on the structural underpinnings of the San Fernando Basin region, which may be important to ground motion models. Gravity data indicate that a deep basin (>5 km) underlies the northern part of the San Fernando Valley; this deep basin is required to explain the lowest gravity values over the Mission Hills thrust fault. Gravity modeling...
Authors
Victoria E. Langenheim, Andrew Griscom, R.C. Jachens, T.G. Hildenbrand
By
Geology, Energy, and Minerals Mission Area, Energy Resources Program, Mineral Resources Program, Science and Decisions Center, Groundwater and Streamflow Information Program, Geology, Minerals, Energy, and Geophysics Science Center
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