Shale, mudstone, and sandstone

Black to gray shale, mudstone, and sandstone with local lenses of pebble conglomerate. Overlies Josephine ophiolite of Harper (1980) (unit Ju)
State Oregon
Name Shale, mudstone, and sandstone
Geologic age Late Jurassic
Lithologic constituents
Sedimentary > Clastic > Mudstone (Bed)Commonly metamorphosed to slate or phyllite
Sedimentary > Clastic > Sandstone > Graywacke (Bed)
Sedimentary > Clastic > Conglomerate (Bed)
Sedimentary > Chemical > Chert (Bed)Present in basal part of unit
Comments Unit is correlative with and lithologically similar to the Galice Formation.

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.

Harper, G.D., 1983, A depositional contact between the Galice Formation and a Late Jurassic ophiolite in northwestern California and southwestern Oregon: Oregon Geology, v. 45, no. 1, p. 3-9.

Harper, G.D., 1980, Structure and petrology of the Josephine Ophiolite and overlying metasedimentary rocks, northwestern California: Berkeley, Calif., University of California, Ph.D. dissertation, 281 p.

NGMDB product
Counties Josephine