Tertiary volcanic flow rocks, unit 10 (Alverson)

Tertiary volcanic flow rocks; minor pyroclastic deposits.
State California
Name Tertiary volcanic flow rocks, unit 10 (Alverson)
Geologic age Tertiary (14-18 Ma)
Lithologic constituents
Major
Igneous > Volcanic > Mafic-volcanic > Andesite (Flow, Volcaniclastic-volcanic breccia, Pyroclastic)
Minor
Igneous > Volcanic > Mafic-volcanic > Basalt (Flow, Volcaniclastic-volcanic breccia, Pyroclastic)
Incidental
Igneous > Volcanic > Mafic-volcanic > Basaltic-andesite (Flow, Volcaniclastic-volcanic breccia, Pyroclastic)
Stratigraphic units Alverson Canyon Formation
References

Todd, V.R., 2004, Preliminary Geologic map of the El Cajon 30 min x 60 min quadrangle, southern California. U.S. Geological Survey Open-file report 2004-1361 (url http://pubs.usgs.gov/of/2004/1361.

https://pubs.er.usgs.gov/publication/ofr20041361

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 Imperial - San Diego