Tertiary intrusive rocks (hypabyssal), unit 9 (Jurassic gabbros along Hayward Fault)

Tertiary intrusive rocks; mostly shallow (hypabyssal) plugs and dikes. Includes some Mesozoic rocks.
State California
Name Tertiary intrusive rocks (hypabyssal), unit 9 (Jurassic gabbros along Hayward Fault)
Geologic age Jurassic
Lithologic constituents
Major
Igneous > Plutonic > Gabbroic > Gabbro (Pluton)
References

Graymer, R.W., 2000, Geologic map and map database of the Oakland metropolitan area, Alameda, Contra Costa, and San Francisco Counties, California: U.S. Geological Survey Miscellaneous Field Studies Map MF-2342, 29 p., scale 1:50,000.

https://pubs.er.usgs.gov/publication/mf2342

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 Alameda - Contra Costa