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Metavolcanic and metasedimentary rocks; Middle to Lower Triassic greenschist-facies metamorphic rocks; western Idaho, Blue Mountains island-arc complex

Middle and Lower Triassic metabasalt and submarine volcaniclastics of western Idaho
State Idaho
Name Metavolcanic and metasedimentary rocks; Middle to Lower Triassic greenschist-facies metamorphic rocks; western Idaho, Blue Mountains island-arc complex
Geologic age Middle and Early Triassic
Comments Metavolcanic rocks include meta-basalt, meta-andesite, keratophyre, metamorphosed pyroclastic breccia, and meta-tuff. Metasedimentary rocks include volcanic-derived meta-conglomerate, metamorphosed epiclastic breccia, arenite, and argillite.
Primary rock type mafic metavolcanic rock
Secondary rock type metasedimentary rock
Other rock types quartzite; meta-conglomerate; meta-argillite; marble; keratophyre
Lithologic constituents
Major
Metamorphic > Metasedimentary (Greenschist)Doyle Creek Fm
Metamorphic > Metavolcanic (Greenschist)Wild Sheep Creek Fm
Map references
Bond, J.G., Kauffman, J.D., Miller, D.A., and Venkatakrishnan, Ramesh, 1978, Geologic map of Idaho: Moscow, Idaho, Idaho Bureau of Mines and Geology, with contributions from U.S. Geological Survey, scale 1:500,000.
Unit references
Bond, J.G., Kauffman, J.D., Miller, D.A., and Venkatakrishnan, Ramesh, 1978, Geologic map of Idaho: Moscow, Idaho, Idaho Bureau of Mines and Geology, with contributions from U.S. Geological Survey, scale 1:500,000.
Vallier, T.L., 1977, The Permian and Triassic Seven Devils Group, western Idaho and northeastern Oregon: U.S. Geological Survey Bulletin 1437, 58 p.
Counties Adams - Idaho - Lewis - Nez Perce - Washington