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Tertiary pyroclastic and volcanic mudflow deposits, unit 5 (Southern California Basin)

Tertiary pyroclastic and volcanic mudflow deposits.
State California
Name Tertiary pyroclastic and volcanic mudflow deposits, unit 5 (Southern California Basin)
Geologic age Tertiary (8-25 Ma)
Primary rock type rhyolite
Secondary rock type tuff
Other rock types andesite; basalt; volcanic breccia (agglomerate)
Lithologic constituents
Major
Igneous > Volcanic > Felsic-volcanic > Dacite (Pyroclastic)
Minor
Igneous > Volcanic > Felsic-volcanic > Dacite (Volcaniclastic, volcanic breccia)
Igneous > Volcanic > Felsic-volcanic > Dacite (Flow)
Igneous > Volcanic > Mafic-volcanic > Andesite (Volcaniclastic, volcanic breccia)
Incidental
Igneous > Volcanic > Mafic-volcanic > Andesite (Pyroclastic)
Igneous > Volcanic > Mafic-volcanic > Basaltic-andesite (Pyroclastic)
Igneous > Volcanic > Mafic-volcanic > Basaltic-andesite (Volcaniclastic, volcanic breccia)
Igneous > Volcanic > Mafic-volcanic > Basalt (Pyroclastic)
Igneous > Volcanic > Mafic-volcanic > Basalt (Volcaniclastic, volcanic breccia)
Map references
Jennings, C.W., Strand, R.G., and Rogers, T.H., 1977, Geologic map of California: California Division of Mines and Geology, scale 1:750,000.
Unit references
Stanley, R.G., Wilson, D.S., and McCrory, P.A., 2000, Locations and ages of middle Tertiary volcanic centers in coastal California: U.S. Geological Survey Open-File Report 00-154, 27 p., url http://geopubs.wr.usgs.gov/open-file/of00-154/
Weigand, P. W., 1982, Middle Cenozoic volcanism of the western Transverse Ranges, in Fife, D. L., and Minch, J. A., eds., Geology and mineral wealth of the California Transverse Ranges: Santa Ana, California, South Coast Geological Society, Inc., p. 170-188.
Weigand, P. W., 1993, Geochemistry and origin of middle Miocene volcanic rocks from Santa Cruz and Anacapa Islands, southern California Borderland, in Hochberg, F. G., ed., Recent advances in California island research: Santa Barbara Museum of Natural History, p. 21-37.
Weigand, P. W., and Savage, K. L., 1993, Review of the petrology and geochemistry of the Miocene Conejo Volcanics of the Santa Monica Mountains, California, in Weigand, P. W., Fritsche, A. E., and Davis, G. E., eds., Miocene sedimentary and volcanic environments, Santa Monica Mountains, California: SEPM (Society for Sedimentary Geology), Pacific Section, Book 72, p. 93-112.
Jennings, C.W., Strand, R.G., and Rogers, T.H., 1977, Geologic map of California: California Division of Mines and Geology, scale 1:750,000.
Counties Los Angeles - Santa Barbara - Ventura