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Geologic Map of the Bodie Hills, California and Nevada

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Geologic Map of the Bodie Hills, California and Nevada Geologic Map of the Bodie Hills, California and Nevada By David A. John, Edward A. du Bray, Stephen E. Box, Peter G. Vikre, James J. Rytuba, Robert J. Fleck, and Barry C. Moring Pamphlet to accompany Scientific Investigations Map 3318 2015 U.S. Department of the Interior U.S. Geological Survey Cover: Photograph showing approximately 6 Ma, flow-banded rhyolite of Big Alkali dome intruding lower Paleozoic metasedimentary rocks at the mouth of Cinnabar Canyon. U.S. Department of the Interior SALLY JEWELL, Secretary U.S. Geological Survey Suzette M. Kimball, Acting Director U.S. Geological Survey, Reston, Virginia: 2015 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment—visit http://www.usgs.gov or call 1-888-ASK-USGS For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Suggested citation: John, D.A., du Bray, E.A., Box, S.E., Vikre, P.G., Rytuba, J.J., Fleck, R.J., and Moring, B.C., 2015, Geologic map of the Bodie Hills, California and Nevada: U.S. Geological Survey Scientific Investigations Map 3318, 64 p., 2 sheets, scale 1:50,000, http://dx.doi.org/10.3133/sim3318. ISSN 2329-132X (online) Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain, it may also contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. Contents Introduction ......................................................................................................................................................................................1 Previous and Present Geologic Mapping .........................................................................................................................................1 Regional Geologic Setting of the Bodie Hills ....................................................................................................................................4 Cenozoic Magmatism in the Bodie Hills ...........................................................................................................................................4 Miocene Magmatism of the Bodie Hills Volcanic Field .................................................................................................................5 Masonic Center ........................................................................................................................................................................5 Mud Spring Canyon Center ....................................................................................................................................................27 East Canyon Center ...............................................................................................................................................................27 Aurora Center .........................................................................................................................................................................27 Rough Creek Center ..............................................................................................................................................................27 Rancheria Center ...................................................................................................................................................................27 West Brawley Peak Center ....................................................................................................................................................27 Trachyandesite of Clark Canyon ............................................................................................................................................28 Bridgeport Canyon Center......................................................................................................................................................28 Del Monte Center ...................................................................................................................................................................28 Aurora Canyon Center ...........................................................................................................................................................28 Mount Biedeman Center ........................................................................................................................................................28 High-Silica Rhyolite Centers...................................................................................................................................................28 Rhyolite of the Bodie Hills ......................................................................................................................................................29 Silver Hill, Potato Peak, and Willow Springs Centers .............................................................................................................29 Big Alkali Center .....................................................................................................................................................................29 Pliocene to Late Pleistocene Magmatism of the Aurora Volcanic Field .....................................................................................29 Miocene Sedimentary Rocks and Deposits ....................................................................................................................................30 Surficial Deposits ...........................................................................................................................................................................30 Structural Geology of the Bodie Hills ..............................................................................................................................................31 Faults .........................................................................................................................................................................................31 Veins and Mineralized Faults .....................................................................................................................................................32 Paleomagnetic Studies and Vertical Axis Rotation of the Bodie Hills .........................................................................................32 Tilting..........................................................................................................................................................................................32 Volcanic Landforms ....................................................................................................................................................................33 Magmatic Doming(?) of the Central Bodie Hills .........................................................................................................................33 Model for Evolution of the Late Cenozoic Stress Field in the Bodie Hills ...................................................................................34 Mineral Deposits and Alteration Zones in the Bodie Hills ...............................................................................................................34 Additional Descriptive Notes ..........................................................................................................................................................35 Description of Map Units ................................................................................................................................................................39 Surficial Deposits .......................................................................................................................................................................39 Rocks of the Aurora Volcanic Field ............................................................................................................................................40 Sedimentary Deposits ................................................................................................................................................................44 Distally Sourced Ash-Flow Tuffs ................................................................................................................................................45 Rocks of the Bodie Hills Volcanic Field ......................................................................................................................................46 Pre-Bodie Hills Volcanic Field Rocks .........................................................................................................................................57 iii Basement Rocks ........................................................................................................................................................................57 References Cited ...........................................................................................................................................................................60 Figures Figure 1. Location map showing regional geologic setting of the Bodie Hills and major physiographic features ........................ 2 Figure
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