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Tertiary pyroclastic and volcanic mudflow deposits, unit 3 (Pinnacles-Neenach)

Tertiary pyroclastic and volcanic mudflow deposits.
State California
Name Tertiary pyroclastic and volcanic mudflow deposits, unit 3 (Pinnacles-Neenach)
Geologic age Tertiary (22-24 Ma)
Primary rock type rhyolite
Secondary rock type dacite
Other rock types ash-flow tuff; ignimbrite; volcanic breccia (agglomerate); tuff
Lithologic constituents
Minor
Igneous > Volcanic > Felsic-volcanic > Rhyolite (Pyroclastic, air fall)
Igneous > Volcanic > Felsic-volcanic > Rhyolite (Pyroclastic, ash-flow)
Igneous > Volcanic > Felsic-volcanic > Rhyolite (Volcaniclastic, volcanic breccia)
Igneous > Volcanic > Felsic-volcanic > Dacite (Volcaniclastic, volcanic breccia)
Incidental
Igneous > Volcanic > Felsic-volcanic > Dacite (Pyroclastic, air fall)
Igneous > Volcanic > Felsic-volcanic > Dacite (Pyroclastic, ash-flow)
Igneous > Volcanic > Mafic-volcanic > Andesite (Pyroclastic, air fall)
Igneous > Volcanic > Mafic-volcanic > Andesite (Pyroclastic, ash-flow)
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/
Matthews, V.,III, 1973, Geology of the Pinnacles volcanic formation and the Neenach volcanic formation and their bearing on the San Andreas fault problem. Unpublished Ph.D dissertation, University of California, Santa Cruz, Santa Cruz, CA.
Weigand, P. W., and Thomas, J. M., 1989, Middle Cenozoic volcanic fields adjacent to the San Andreas fault, central California: Correlation and petrogenesis: in Baldwin, E. J., Foster, J. H., Lewis, W. L., and Hardy, J. K., eds., San Andreas fault - Cajon Pass to Wallace Creek: South Coast Geological Society Guidebook, no. 17, vol. 1, p. 207-222.
Ludington, Steve, and Gray, Karen, 1987, Petrochemical studies of the Pinnacles Wilderness contiguous wilderness study area, Monterey and San Benito Counties, California. U.S. Geological Survey Open-file report 87-135, 9 p.
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 Monterey - San Benito