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Tertiary pyroclastic and volcanic mudflow deposits, unit 1 (Sonoma Volcanic Field)

Tertiary pyroclastic and volcanic mudflow deposits.
State California
Name Tertiary pyroclastic and volcanic mudflow deposits, unit 1 (Sonoma Volcanic Field)
Geologic age Tertiary (3-7 Ma)
Comments includes pantellerites
Primary rock type rhyolite
Secondary rock type dacite
Other rock types andesite; ash-flow tuff; ignimbrite; tuff
Lithologic constituents
Major
Igneous > Volcanic > Felsic-volcanic > Rhyolite (Pyroclastic, ash-flow)
Igneous > Volcanic > Felsic-volcanic > Dacite (Pyroclastic, ash-flow)
Minor
Igneous > Volcanic > Felsic-volcanic > Rhyolite (Pyroclastic, air fall)
Igneous > Volcanic > Felsic-volcanic > Dacite (Pyroclastic, air fall)
Incidental
Igneous > Volcanic > Felsic-volcanic > Rhyolite (Flow)
Igneous > Volcanic > Felsic-volcanic > Dacite (Flow)
Igneous > Volcanic > Mafic-volcanic > Andesite (Pyroclastic, air fall)
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
Whitlock, Jaime S., 2002, Evidence of a mantle wedge source for slab window volcanism in the northern California coast ranges. Unpublished M.S. Thesis, the Pennsylvania State University, College Station, Pennsylvania, 78 p.
McLaughlin, R.J., and Sarna-Wojcicki, A., 2003, Geology of the Right Stepover Region between the Rodgers Creek, Healdsburg, and Maacama Faults, Northern San Francisco Bay Region. U.S. Geological Survey Open-File Report 03-502, 23 p., url http://geopubs.wr.usgs.gov/open-file/of03-502/
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 Lake - Napa - Sonoma