Three-dimensional geologic mapping of the Cenozoic basin fill, Amargosa Desert basin, Nevada and California

Scientific Investigations Report 2014-5003
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Abstract

Understanding the subsurface geologic framework of the Cenozoic basin fill that underlies the Amargosa Desert in southern Nevada and southeastern California has been improved by using borehole data to construct three-dimensional lithologic and interpreted facies models. Lithologic data from 210 boreholes from a 20-kilometer (km) by 90-km area were reduced to a limited suite of descriptors based on geologic knowledge of the basin and distributed in three-dimensional space using interpolation methods. The resulting lithologic model of the Amargosa Desert basin portrays a complex system of interfingered coarse- to fine-grained alluvium, playa and palustrine deposits, eolian sands, and interbedded volcanic units. Lithologic units could not be represented in the model as a stacked stratigraphic sequence due to the complex interfingering of lithologic units and the absence of available time-stratigraphic markers. Instead, lithologic units were grouped into interpreted genetic classes, such as playa or alluvial fan, to create a three-dimensional model of the interpreted facies data. Three-dimensional facies models computed from these data portray the alluvial infilling of a tectonically formed basin with intermittent internal drainage and localized regional groundwater discharge. The lithologic and interpreted facies models compare favorably to resistivity, aeromagnetic, and geologic map data, lending confidence to the interpretation.

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Publication type Report
Publication Subtype USGS Numbered Series
Title Three-dimensional geologic mapping of the Cenozoic basin fill, Amargosa Desert basin, Nevada and California
Series title Scientific Investigations Report
Series number 2014-5003
DOI 10.3133/sir20145003
Year Published 2014
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Geosciences and Environmental Change Science Center
Description Report: v, 40 p.; Appendix 1: 1 XLS file; Appendix 2: XLS file
Country United States
State California;Nevada
Datum North American Datum of 1927
Projection Universal Transverse Mercator, Zone 11
Scale 100000
Additional Online Files (Y/N) Y
Google Analytic Metrics Metrics page
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