| State | California |
|---|---|
| Name | Tertiary intrusive rocks (hypabyssal), unit 4 (Tranquillon-Obispo) |
| Geologic age | Tertiary |
| Lithologic constituents |
Major
Igneous > Hypabyssal > Felsic-hypabyssal > Hypabyssal-rhyolite (Pluton, Dike or sill)
Minor
Igneous > Hypabyssal > Felsic-hypabyssal > Hypabyssal-dacite (Pluton)
Incidental
Igneous > Hypabyssal > Mafic-hypabyssal > Hypabyssal-andesite (Pluton)
Igneous > Hypabyssal > Mafic-hypabyssal > Hypabyssal-basalt (Pluton)
|
| Comments | includes Morro Rock intrusions |
| References | Luyendyk, B.P., Gans, P., and Kamerling, M.J., 1998, 40Ar/39Ar geochronology of Southern California Neogene volcanism. AAPG Bulleting, v. 82, p. 852 (abstract)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/https://pubs.er.usgs.gov/publication/ofr00154 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 | San Luis Obispo |