| State | California |
|---|---|
| Name | Tertiary volcanic flow rocks, unit 3 (Sonoma Volcanic Field) |
| Geologic age | Tertiary (3-7 Ma) |
| Lithologic constituents |
Major
Igneous > Volcanic > Felsic-volcanic > Dacite (Flow, Pyroclastic, Dome)
Minor
Igneous > Volcanic > Felsic-volcanic > Rhyolite (Flow, Pyroclastic, Dome)
Incidental
Igneous > Volcanic > Mafic-volcanic > Basalt (Flow, Pyroclastic)
Igneous > Volcanic > Mafic-volcanic > Basaltic-andesite (Flow)
Igneous > Volcanic > Mafic-volcanic > Andesite (Flow)
|
| Stratigraphic units | Sonoma Volcanics, St. Helena Rhyolite |
| 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 Unpublished M.S. Thesis, the Pennsylvania State University, College Station, Pennsylvania, 78 p.McLaughlin, R.J., and Sarna-Wojcicki, A., 2003, Geology of the Right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/https://pubs.er.usgs.gov/publication/ofr03502 Jennings, C.W., Strand, R.G., Rogers, T.H., Boylan, R.T., Moar, R.R., and Switzer, R.A., 1977, Geologic Map of California: California Division of Mines and Geology, Geologic Data Map 2, scale 1:750,000. |
| NGMDB product | |
| Counties | Lake - Napa - Solano - Sonoma |