| State | California |
|---|---|
| Name | Tertiary-Cretaceous Coastal Belt Rocks |
| Geologic age | Late Cretaceous to Pliocene |
| Lithologic constituents |
Major
Sedimentary > Clastic > Mudstone (Bed)Penetratively sheared; commonly forms matrix of melange enclosing other rocks of unit
Sedimentary > Clastic > Sandstone (Bed)Feldspathic to arkosic. Commonly cut by laumontite veins; commonly contains fine-grained prehnite and pumpellyite. Ranges from partially disrupted to melange
Minor
Sedimentary > Clastic > Conglomerate (Bed)
Incidental
Igneous > Volcanic > Mafic-volcanic > Basalt (Flow, Pyroclastic-tuff, Dike or sill)Commonly forms blocks in melange
Sedimentary > Chemical > Chert (Bed)Radiolarian chert
Metamorphic > Schist (Blueschist)Forms blocks in melange locally along eastern boundaries of unit
Sedimentary > Carbonate > Limestone (Lens)Pelagic limestone interbedded with basalt
|
| Comments | Comprises Coastal terrane and most of King Range terrane (Franciscan Complex) in northwestern California. These units contain the youngest rocks known in the Franciscan Complex. Penetratively sheared and structurally disrupted; includes melange |
| Stratigraphic units | Coastal Belt of Franciscan Complex (part); Coastal terrane; King Range terrane (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.Strand, R.G., 1962, Geologic map of California, Olaf P. Jenkins edition, Redding sheet, scale 1:250,000.Koenig, J.B., 1963, Geologic map of California, Olaf P. Jenkins edition, Santa Rosa sheet, scale 1:250,000.Jennings, C.W., and Strand, R.G., 1960, Geologic map of California, Olaf P. Jenkins edition, Ukiah sheet, scale 1:250,000.Wagner, D.L., and Bortugno, E.J., 1982, Geologic map of the Santa Rosa quadrangle, California: California Division of Mines and Geology, Regional Geologic Map Series, Map 2A, scale 1:250,000.Jayko, A.S., Blake, M.C., Jr., McLaughlin, R.J., Ohlin, H.N., Ellen, S.D., and Kelsey, Harvey, 1989, Reconnaissance geologic map of the Covelo 30- by 60-minute quadrangle, northern California: U.S. Geological Survey Miscellaneous Field Studies Map MF-2001, scale 1:100,000.https://pubs.er.usgs.gov/publication/mf2001 McLaughlin, R.J., Ellen, S.D., Blake, M.C., Jr., Jayko, A.S., Irwin, W.P., Aalto, K.R., Carver, G.A., and Clarke, S.H., Jr., 2000, Geology of the Cape Mendocino, Eureka, Garberville, and southwestern part of the Hayfork 30 x 60 minute quadrangles and adjacent offshore area, northern California: U.S. Geological Survey Miscellaneous Field Studies Map MF-2336, 30 p., scale 1:100,000.https://pubs.er.usgs.gov/publication/mf2336 Silberling, N.J., Jones, D.L., Blake, M.C., Jr., and Howell, D.G., 1987, Lithotectonic terrane map of the western conterminous United States: U.S. Geological Survey Miscellaneous Field Studies Map MF-1874-C, scale 1:2,500,000.https://pubs.er.usgs.gov/publication/mf1874C Blake, M.C., Jr., and Jones, D.L., 1981, The Franciscan Assemblage and related rocks in northern California: a reinterpretation, in Ernst, W.G., ed., The geotectonic development of California (Rubey Volume 1): Englewood Cliffs, N.J., Prentice-Hall, p. 307-328.Blake, M.C., Jr., Jayko, A.S., McLaughlin, R.J., and Underwood, M.B., 1988, Metamorphic and tectonic evolution of the Franciscan Complex, northern California, in Ernst, W.G., ed., Metamorphism and crustal evolution of the western United States (Rubey Volume 7): Englewood Cliffs, N.J., Prentice-Hall, p. 1035-1060.Blake, M.C., Jr., and others, 1985, C-1 Mendocino triple junction to North American craton: Geological Society of America Centennial Continent/Ocean Transect 12, 30 p., scale 1:500,000.McLaughlin, R.J., Sliter, W.V., Frederiksen, N.O., Harbert, W.P., and McCulloch, D.S., 1994, Plate motions recorded in tectonostratigraphic terranes of the Franciscan Complex and evolution of the Menocino triple junction, northwestern California: U.S. Geological Survey Bulletin 1997, 60 p.https://pubs.er.usgs.gov/publication/b1997 |
| NGMDB product | |
| Counties | Humboldt - Mendocino - Sonoma |