Amphibolite of Briggs Creek

Informally called the "Briggs Creek amphibolite" by Garcia (1976) and by Coleman and others (1976). Consists of amphibolite, micaceous quartzite, quartz schist, and recrystallized manganiferous chert. Includes structurally complex amphibole schist and quartz-rich hornblende gneiss of unknown age exposed at and near Chetco Peak west of Cave Junction (Smith and others, 1982)
State Oregon
Name Amphibolite of Briggs Creek
Geologic age Paleozoic or Mesozoic
Lithologic constituents
Major
Metamorphic > Amphibolite
Minor
Metamorphic > Metasedimentary > Metaclastic > Quartzite
Metamorphic > Schist
Incidental
Metamorphic > Gneiss
Sedimentary > Chemical > Chert
References

Walker, G.W. and MacLeod, N.S., 1991, Geologic map of Oregon: U.S. Geological Survey, scale 1:500,000.

Irwin, W.P., 1994, Geologic map of the Klamath Mountains, California and Oregon: U.S. Geological Survey Miscellaneous Investigations Series Map I-2148, scale 1:500,000.

https://pubs.er.usgs.gov/publication/i2148

Saleeby, J..B., and Harper, G.D., 1993, Tectonic relations between the Galice Formation and the Condrey Mountain Schist, Klamath Mountains, Northern California, in Dunne, G.C., and McDougall, K.A., eds., Mesozoic paleogeography of the western United States - II: Pacific Section Society of Economic Paleontologists and Mineralogists, Book 71, p. 61-80.

Blake, M.C., Jr., Engebretson, D.C., Jayko, A.S., and Jones, D.L., 1985, Tectonostratigraphic terranes in southwest Oregon, in Howell, D.G., ed., Tectonostratigraphic terranes of the circum-Pacific region: Circum-Pacific Council for Energy and Mineral Resources Earth Science Series, v. 1, p. 147-158.

Smith, J.G., Page, N.J, Johnson, M.G., Moring, B.C., and Gray, F., 1982, Preliminary geologic map of the Medford 1ø by 2ø quadrangle, Oregon and California: U.S. Geological Survey Open-File Report 82-955, scale 1:250,000.

https://pubs.er.usgs.gov/publication/ofr82955

Garcia, M.O., 1976, Rogue River island arc complex, western Jurassic belt, Klamath Mountains, Oregon: Geological Society of America Abstracts with Programs, v. 8, no. 3, p. 375.

Coleman, R.G., Garcia, M., and Anglin, C., 1976, The amphibolite of Briggs Creek: a tectonic slice of metamorphosed oceanic crust in southwestern Oregon: Geological Society of America Abstracts with Programs, v. 8, no. 3, p. 363.

NGMDB product
Counties Curry - Josephine