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Summary of geophysical investigations of the Death Valley regional water-flow modeling project, Nevada and California

Richard J. Blakely·Victoria E. Langenheim·David A. Ponce
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Abstract

This report summarizes geophysical investigations in the Amargosa Desert and surrounding areas conducted between 1997 and 2000 in support of the Death Valley Regional Water-Flow Modeling Project of the U.S. Geological Survey. These investigations used both gravity and aeromagnetic data to develop a regional-scale tectonic and lithologic model for the near-surface. Gravity data were inverted in order to estimate the depth to pre-Cenozoic basement throughout the study area. This basement surface is interpreted to be the contact between pre-Cenozoic carbonate rocks and overlying alluvium, an important component of water-flow models. Gravity data also were used to identify locations where basement rocks are anomalously dense, possibly indicating areas resistant to water flow. A new aeromagnetic survey of the central part of the study area was used to map concealed faults and areas underlain by volcanic rocks.

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Richard J. Blakely, Victoria E. Langenheim, David A. Ponce. 2000. Summary of geophysical investigations of the Death Valley regional water-flow modeling project, Nevada and California. https://doi.org/10.3133/ofr00189

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