| State | California |
|---|---|
| Name | Permian marine sedimentary rocks, unit 2 (Northwestern Sierra Nevada) |
| Geologic age | Paleozoic or Mesozoic |
| Lithologic constituents |
Major
Metamorphic > Metasedimentary > Metaclastic > Phyllite (Amphibolite)Quartz-biotite-muscovite phyllite; locally contains andalusite, staurolite, garnet, and cordierite.
Minor
Metamorphic > Metasedimentary > Metaclastic > QuartziteInterbedded with phyllite
Metamorphic > Metasedimentary > Metacarbonate > MarbleLenticular bodies
Sedimentary > Chemical > Chert (Bed)Interbedded with phyllite
Incidental
Sedimentary > Clastic > Conglomerate (Bed)Interbedded with quartzite; clasts are quartzite or chert
|
| Comments | Northwestern Sierra Nevada. Consists primarily of phyllite, marble, and quartzite (metasedimentary rocks of the Horseshoe Bend Formation). Assigned a Permian(?) age by Hietanen (1973) based on tentative lithologic correlation with dated rocks to east. |
| Stratigraphic units | Horseshoe Bend Fm. (part) |
| 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.Saucedo, G.J., and Wagner, D.L., 1992, Geologic map of the Chico quadrangle, California: California Division of Mines and Geology, Regional Geologic Map Series, Map 7A, scale 1:250,000.Hietanen, A., 1981, The Feather River area as a part of the Sierra Nevada suture system in California: U.S. Geological Survey Professional Paper 1226-B, 13 p.https://pubs.er.usgs.gov/publication/pp1226AC Hietanen, A., 1973, Geology of the Pulga and Bucks Lake quadrangles, Butte and Plumas Counties, California: U.S. Geological Survey Professional Paper 731, 66 p.https://pubs.er.usgs.gov/publication/pp731 |
| NGMDB product | |
| Counties | Butte - Plumas |