USGS Open-File Report 2013–1024-H: Gravity Survey and Interpretation of Fort Irwin and Vicinity, Mojave Desert, California

Gravity Survey and Interpretation of Fort Irwin and Vicinity, Mojave Desert, California

By R.C. Jachens and V.E. Langenheim

Abstract

In support of a hydrogeologic study of the groundwater resources on Fort Irwin, we have combined new gravity data with preexisting measurements to produce an isostatic residual gravity map, which we then separated into two components reflecting (1) the density distribution in the pre-Cenozoic basement complex and (2) the distribution of low-density Cenozoic volcanic and sedimentary deposits that lie on top of the basement complex. The second component was inverted to estimate the three-dimensional distribution of Cenozoic deposits by using constraints from geology, drillholes, and time-domain electromagnetic soundings. In most of the base, the Cenozoic deposits are no more than 300 m thick, except in the basins with more than 500 m of fill beneath Coyote Lake, Red Pass Lake, west of Nelson Lake, west of Superior Lake, Bicycle Lake, and in the vicinity of Nelson Lake.

First posted November 26, 2014

This report is only available on-line

Back to Geology and Geophysics Applied to Groundwater Hydrology at Fort Irwin, California

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Suggested citation:

Jachens, R.C., and Langenheim, V.E., 2014, Gravity survey and interpretation of Fort Irwin and vicinity, Mojave Desert, California, chap. H of Buesch, D.C., ed., Geology and geophysics applied to groundwater hydrology at Fort Irwin, California: U.S. Geological Survey Open-File Report 2013–1024, 11 p. http://dx.doi.org/10.3133/ofr20131024H.

ISSN 2331-1258 (online)

Contents

Abstract

Introduction

Datasets

Gravity Field

Thickness of Cenozoic Deposits Estimated from Gravity Data

Acknowledgments

References

Figures (5)

Tables (1)

Prepared in cooperation with the U.S. Army, Fort Irwin National Training Center

Gravity Survey and Interpretation of Fort Irwin and Vicinity, Mojave Desert, California

By R.C. Jachens and V.E. Langenheim

Abstract

Suggested citation:

Contents