Generalized Surficial Geologic Map of the Fort Irwin Area, San Bernardino County, California
Links
- Document: Report (pdf)
- Plate: Map (pdf)
- Larger Work: This publication is Chapter B of Geology and geophysics applied to groundwater hydrology at Fort Irwin, California
- Database: Database (zip)
- NGMDB Index Page: National Geologic Map Database Index Page
- Download citation as: RIS | Dublin Core
Abstract
The geology and landscape of the Fort Irwin area, typical of many parts of the Mojave Desert, consist of rugged mountains separated by broad alluviated valleys that form the main coarse-resolution features of the geologic map. Crystalline and sedimentary rocks, Mesozoic and older in age, form most of the mountains with lesser accumulations of Miocene sedimentary and volcanic rocks. In detail, the area exhibits a fairly complex distribution of surficial deposits resulting from diverse rock sources and geomorphology that has been driven by topographic changes caused by recent and active faulting. Depositional environments span those typical of the Mojave Desert: alluvial fans on broad piedmonts, major intermittent streams along valley floors, eolian sand dunes and sheets, and playas in closed valleys that lack through-going washes. Erosional environments include rocky mountains, smooth gently sloping pediments, and badlands in readily eroded sediment. All parts of the landscape, from regional distribution of mountains, valleys, and faults to details of degree of soil development in surface materials, are portrayed by the surficial geologic map. Many of these attributes govern infiltration and recharge, and the surface distribution of permeable rock units such as Miocene sedimentary and volcanic rocks provides a basis for evaluating potential groundwater storage. Quaternary faults are widespread in the Fort Irwin area and include sinistral, east-striking faults that characterize the central swath of the area and the contrasting dextral, northwest-striking faults that border the east and west margins. Bedrock distribution and thickness of valley-fill deposits are controlled by modern and past faulting, and faults on the map help to identify targets for groundwater exploration.
Suggested Citation
Miller, D.M., Menges, C.M., and Lidke, D.J., 2014, Generalized surficial geologic map of the Fort Irwin area, San Bernardino County, California, chap. B 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., scale 1:100,000, https://doi.org/10.3133/ofr20131024B.
ISSN: 2331-1258 (online)
Study Area
| Publication type | Report |
|---|---|
| Publication Subtype | USGS Numbered Series |
| Title | Generalized surficial geologic map of the Fort Irwin Area, San Bernardino County, California |
| Series title | Open-File Report |
| Series number | 2013-1024 |
| Chapter | B |
| DOI | 10.3133/ofr20131024B |
| Year Published | 2014 |
| Language | English |
| Publisher | U.S. Geological Survey |
| Publisher location | Reston, VA |
| Contributing office(s) | Geology, Minerals, Energy, and Geophysics Science Center, Geosciences and Environmental Change Science Center |
| Description | Report: iii, 11 p.; 1 Plate: 50.91 x 35.84 inches; Database |
| Larger Work Type | Report |
| Larger Work Subtype | USGS Numbered Series |
| Larger Work Title | Geology and geophysics applied to groundwater hydrology at Fort Irwin, California |
| Country | United States |
| State | California |
| County | San Bernardino County |
| Other Geospatial | Fort Irwin area |
| Scale | 100000 |
| Online Only (Y/N) | Y |
| Additional Online Files (Y/N) | Y |
| Google Analytic Metrics | Metrics page |