Victoria Langenheim
Vickie is a Research Geophysicist with the Geology, Minerals, Energy, and Geophysics Science Center
Science and Products
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
Filter Total Items: 191
Neogene contraction between the San Andreas fault and the Santa Clara Valley, San Francisco Bay region, California Neogene contraction between the San Andreas fault and the Santa Clara Valley, San Francisco Bay region, California
In the southern San Francisco Bay region of California, oblique dextral reverse faults that verge northeastward from the San Andreas fault experienced triggered slip during the 1989 M7.1 Loma Prieta earthquake. The role of these range-front thrusts in the evolution of the San Andreas fault system and the future seismic hazard that they may pose to the urban Santa Clara Valley are poorly...
Authors
Robert J. McLaughlin, V.E. Langenheim, K. M. Schmidt, R.C. Jachens, R. G. Stanley, A. S. Jayko, K. A. McDougall, J. C. Tinsley, Z. C. Valin
Interpretation of an aeromagnetic survey over part of Virgin Valley, Tule Desert, and the valley surrounding Meadow Valley Wash, southeastern Nevada Interpretation of an aeromagnetic survey over part of Virgin Valley, Tule Desert, and the valley surrounding Meadow Valley Wash, southeastern Nevada
No abstract available.
Authors
R.C. Jachens, D.L. Dixon, V.E. Langenheim, R. L. Morin
Preliminary geologic map of the Valley Quadrangle, Clark County, Nevada Preliminary geologic map of the Valley Quadrangle, Clark County, Nevada
No abstract available.
Authors
S.C. Lundstrom, W. R. Page, V.E. Langenheim, O.D. Young, S. A. Mahan, G. L. Dixon
Thickness of Cenozoic deposits and location and geometry of the Las Vegas Valley shear zone, Nevada, based on gravity, seismic-reflection, and aeromagnetic data Thickness of Cenozoic deposits and location and geometry of the Las Vegas Valley shear zone, Nevada, based on gravity, seismic-reflection, and aeromagnetic data
No abstract available.
Authors
V.E. Langenheim, John Grow, J. J. Miller, J. D. Davidson, E. Robison
Three-dimensional model of Paleozoic basement beneath Amargosa Desert and Pahrump Valley, California and Nevada: Implications for tectonic evolution and water resources Three-dimensional model of Paleozoic basement beneath Amargosa Desert and Pahrump Valley, California and Nevada: Implications for tectonic evolution and water resources
No abstract available.
Authors
R.J. Blakely, R. L. Morin, E.H. McKee, K. M. Schmidt, V.E. Langenheim, G. L. Dixon
Implications of seismic reflection and potential field geophysical data on the structural framework of the Yucca Mountain-Crater Flat region, Nevada Implications of seismic reflection and potential field geophysical data on the structural framework of the Yucca Mountain-Crater Flat region, Nevada
Seismic reflection and gravity profiles collected across Yucca Mountain, Nevada, together with geologic data, provide evidence against proposed active detachment faults at shallow depth along the pre-Tertiary–Tertiary contact beneath this potential repository for high-level nuclear waste. The new geophysical data show that the inferred pre-Tertiary–Tertiary contact is offset by moderate-...
Authors
T.M. Brocher, W.C. Hunter, V.E. Langenheim
Preliminary location and geometry of the Las Vegas Valley shear zone based on gravity and aeromagnetic data Preliminary location and geometry of the Las Vegas Valley shear zone based on gravity and aeromagnetic data
No abstract available.
Authors
V.E. Langenheim, R.C. Jachens, K. M. Schmidt
Aeromagnetic map of the Los Angeles 1:100,000-scale quadrangle, California Aeromagnetic map of the Los Angeles 1:100,000-scale quadrangle, California
No abstract available.
Authors
V.E. Langenheim, R.C. Jachens
Commerce geophysical lineament - Its source, geometry, and relation to the Reelfoot rift and New Madrid seismic zone Commerce geophysical lineament - Its source, geometry, and relation to the Reelfoot rift and New Madrid seismic zone
The Commerce geophysical lineament is a northeast-trending magnetic and gravity feature that extends from central Arkansas to southern Illinois over a distance of ≈400 km. It is parallel to the trend of the Reelfoot graben, but offset ≈40 km to the northwest of the western margin of the rift floor. Modeling indicates that the source of the aeromagnetic and gravity anomalies is probably a...
Authors
V.E. Langenheim, T.G. Hildenbrand
Coseismic deformation during the 1989 Loma Prieta earthquake and range-front thrusting along the southwestern margin of the Santa Clara Valley, California Coseismic deformation during the 1989 Loma Prieta earthquake and range-front thrusting along the southwestern margin of the Santa Clara Valley, California
Damage patterns caused by the 1989 Loma Prieta earthquake along the southwestern margin of the Santa Clara Valley, California, form three zones that coincide with mapped and inferred traces of range-front thrust faults northeast of the San Andreas fault. Damage in these zones was largely contractional, consistent with past displacement associated with these faults. The damage zones...
Authors
V.E. Langenheim, K. M. Schmidt, R.C. Jachens
Thickness and storage capacity of basin fill of the northern part of the Eldorado Valley, Nevada, and the extent of the Boulder City Pluton Thickness and storage capacity of basin fill of the northern part of the Eldorado Valley, Nevada, and the extent of the Boulder City Pluton
No abstract available.
Authors
V.E. Langenheim, K. M. Schmidt
Thickness of Cenozoic deposits and groundwater storage capacity of the westernmost part of the Las Vegas Valley, Nevada, inferred from gravity data Thickness of Cenozoic deposits and groundwater storage capacity of the westernmost part of the Las Vegas Valley, Nevada, inferred from gravity data
No abstract available.
Authors
V.E. Langenheim, R.C. Jachens
Science and Products
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
Filter Total Items: 191
Neogene contraction between the San Andreas fault and the Santa Clara Valley, San Francisco Bay region, California Neogene contraction between the San Andreas fault and the Santa Clara Valley, San Francisco Bay region, California
In the southern San Francisco Bay region of California, oblique dextral reverse faults that verge northeastward from the San Andreas fault experienced triggered slip during the 1989 M7.1 Loma Prieta earthquake. The role of these range-front thrusts in the evolution of the San Andreas fault system and the future seismic hazard that they may pose to the urban Santa Clara Valley are poorly...
Authors
Robert J. McLaughlin, V.E. Langenheim, K. M. Schmidt, R.C. Jachens, R. G. Stanley, A. S. Jayko, K. A. McDougall, J. C. Tinsley, Z. C. Valin
Interpretation of an aeromagnetic survey over part of Virgin Valley, Tule Desert, and the valley surrounding Meadow Valley Wash, southeastern Nevada Interpretation of an aeromagnetic survey over part of Virgin Valley, Tule Desert, and the valley surrounding Meadow Valley Wash, southeastern Nevada
No abstract available.
Authors
R.C. Jachens, D.L. Dixon, V.E. Langenheim, R. L. Morin
Preliminary geologic map of the Valley Quadrangle, Clark County, Nevada Preliminary geologic map of the Valley Quadrangle, Clark County, Nevada
No abstract available.
Authors
S.C. Lundstrom, W. R. Page, V.E. Langenheim, O.D. Young, S. A. Mahan, G. L. Dixon
Thickness of Cenozoic deposits and location and geometry of the Las Vegas Valley shear zone, Nevada, based on gravity, seismic-reflection, and aeromagnetic data Thickness of Cenozoic deposits and location and geometry of the Las Vegas Valley shear zone, Nevada, based on gravity, seismic-reflection, and aeromagnetic data
No abstract available.
Authors
V.E. Langenheim, John Grow, J. J. Miller, J. D. Davidson, E. Robison
Three-dimensional model of Paleozoic basement beneath Amargosa Desert and Pahrump Valley, California and Nevada: Implications for tectonic evolution and water resources Three-dimensional model of Paleozoic basement beneath Amargosa Desert and Pahrump Valley, California and Nevada: Implications for tectonic evolution and water resources
No abstract available.
Authors
R.J. Blakely, R. L. Morin, E.H. McKee, K. M. Schmidt, V.E. Langenheim, G. L. Dixon
Implications of seismic reflection and potential field geophysical data on the structural framework of the Yucca Mountain-Crater Flat region, Nevada Implications of seismic reflection and potential field geophysical data on the structural framework of the Yucca Mountain-Crater Flat region, Nevada
Seismic reflection and gravity profiles collected across Yucca Mountain, Nevada, together with geologic data, provide evidence against proposed active detachment faults at shallow depth along the pre-Tertiary–Tertiary contact beneath this potential repository for high-level nuclear waste. The new geophysical data show that the inferred pre-Tertiary–Tertiary contact is offset by moderate-...
Authors
T.M. Brocher, W.C. Hunter, V.E. Langenheim
Preliminary location and geometry of the Las Vegas Valley shear zone based on gravity and aeromagnetic data Preliminary location and geometry of the Las Vegas Valley shear zone based on gravity and aeromagnetic data
No abstract available.
Authors
V.E. Langenheim, R.C. Jachens, K. M. Schmidt
Aeromagnetic map of the Los Angeles 1:100,000-scale quadrangle, California Aeromagnetic map of the Los Angeles 1:100,000-scale quadrangle, California
No abstract available.
Authors
V.E. Langenheim, R.C. Jachens
Commerce geophysical lineament - Its source, geometry, and relation to the Reelfoot rift and New Madrid seismic zone Commerce geophysical lineament - Its source, geometry, and relation to the Reelfoot rift and New Madrid seismic zone
The Commerce geophysical lineament is a northeast-trending magnetic and gravity feature that extends from central Arkansas to southern Illinois over a distance of ≈400 km. It is parallel to the trend of the Reelfoot graben, but offset ≈40 km to the northwest of the western margin of the rift floor. Modeling indicates that the source of the aeromagnetic and gravity anomalies is probably a...
Authors
V.E. Langenheim, T.G. Hildenbrand
Coseismic deformation during the 1989 Loma Prieta earthquake and range-front thrusting along the southwestern margin of the Santa Clara Valley, California Coseismic deformation during the 1989 Loma Prieta earthquake and range-front thrusting along the southwestern margin of the Santa Clara Valley, California
Damage patterns caused by the 1989 Loma Prieta earthquake along the southwestern margin of the Santa Clara Valley, California, form three zones that coincide with mapped and inferred traces of range-front thrust faults northeast of the San Andreas fault. Damage in these zones was largely contractional, consistent with past displacement associated with these faults. The damage zones...
Authors
V.E. Langenheim, K. M. Schmidt, R.C. Jachens
Thickness and storage capacity of basin fill of the northern part of the Eldorado Valley, Nevada, and the extent of the Boulder City Pluton Thickness and storage capacity of basin fill of the northern part of the Eldorado Valley, Nevada, and the extent of the Boulder City Pluton
No abstract available.
Authors
V.E. Langenheim, K. M. Schmidt
Thickness of Cenozoic deposits and groundwater storage capacity of the westernmost part of the Las Vegas Valley, Nevada, inferred from gravity data Thickness of Cenozoic deposits and groundwater storage capacity of the westernmost part of the Las Vegas Valley, Nevada, inferred from gravity data
No abstract available.
Authors
V.E. Langenheim, R.C. Jachens