Jurassic marine rocks, unit 4 (Peninsular Ranges and Western Transverse Ranges)

Shale, sandstone, minor conglomerate, chert, slate, limestone; minor pyroclastic rocks
State California
Name Jurassic marine rocks, unit 4 (Peninsular Ranges and Western Transverse Ranges)
Geologic age Paleozoic(?) to Late Jurassic
Lithologic constituents
Major
Metamorphic > Metasedimentary > Metaclastic > Argillite
Minor
Sedimentary > Clastic > Sandstone > Graywacke (Bed)Lithic graywacke
Metamorphic > Metasedimentary > Metaclastic > QuartziteFeldspathic to arkosic quartzite
Metamorphic > SchistGradational with phyllite
Metamorphic > Metasedimentary > Metaclastic > PhylliteGradational with schist
Incidental
Igneous > Volcanic > Ultramafic
Sedimentary > Clastic > Conglomerate (Bed)Commonly metamorphosed
Metamorphic > AmphiboliteThin lenses, possibly metamorphosed sills
Sedimentary > Chemical > ChertGenerally metamorphosed
Sedimentary > Carbonate > Limestone (Bed)Rarely fossiliferous
Metamorphic > GneissCommonly derived from impure quartzite
Metamorphic > Metasedimentary > Metacarbonate > Marble
Comments Southwestern California, Peninsular Ranges. Primarily fine-grained pelitic rocks and graywacke, variably metamorphosed. May include some rocks of Paleozoic age
Stratigraphic units Bedford Canyon Fm., Santa Monica Slate, French Valley Fm.
References

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.

Jennings, C.W., 1985, An explanatory text to accompany the 1:750,000 scale fault and geologic maps of California: California Division of Mines and Geology, Bulletin 201, 197 p.

Jennings, C.W., and Strand, R.G., 1969, Geologic map of California, Olaf P. Jenkins edition, Los Angeles sheet, scale 1:250,000.

Strand, R.G., 1962, Geologic map of California, Olaf P. Jenkins edition, San Diego-El Centro sheet, scale 1:250,000.

Rogers, T.H., 1966, Geologic map of California, Olaf P. Jenkins edition, Santa Ana sheet, scale 1:250,000.

Morton, D.M., 1999, Preliminary digital geologic map of the Santa Ana 30' x 60' quadrangle, southern California: U.S. Geological Survey Open-File Report 99-172, scale 1:100,000.

https://pubs.er.usgs.gov/publication/ofr99172

Criscione, J.J., Davis, T.E., and Ehlig, P., 1978, The age of sedimentation/diagenesis for the Bedford Canyon Formation and the Santa Monica Formation of southern California: a Rb/Sr evaluation, in Howell, D.G., and McDougall, K.A., eds., Mesozoic paleogeography of the western United States: Society of Economic Paleontologists and Mineralogists, Pacific Section, Pacific Coast Paleogeography Symposium 2, p. 385-396.

Weber, F.H., Jr., 1963, Geology and mineral resources of San Diego County, California: California Division of Mines and Geology, County Report 3, 309 p., scale 1:125,000.

Gastil, Gordon, Morgan, George, and Krummenacher, Daniel, 1981, The tectonic history of peninsular California and adjacent Mexico, in Ernst, W.G., ed., The geotectonic development of California (Rubey Volume 1): Englewood Cliffs, N.J., Prentice-Hall, p. 284-306.

Schwarcz, H.P., 1969, Pre-Cretaceous sedimentation and metamorphism in the Winchester area, northern Peninsular Ranges, California: Geological Society of America Special Paper 100, 63 p.

NGMDB product
Counties Los Angeles - Orange - Riverside - San Diego