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Sedimentary and volcanic rocks (Upper? Triassic)

Undifferentiated marine sedimentary rocks and volcanic rocks, locally slightly to moderately metamorphosed, of Late(?) Triassic age, exposed principally in Hells Canyon of Snake River, locally in tributary canyons of Imnaha River, and in several areas marginal to the Wallowa Mountains
State Oregon
Name Sedimentary and volcanic rocks (Upper? Triassic)
Geologic age Late Triassic
Primary rock type mixed clastic/volcanic
Secondary rock type
Other rock types
Lithologic constituents
Map references
Walker, G.W. and MacLeod, N.S., 1991, Geologic map of Oregon: U.S. Geological Survey, scale 1:500,000.
Unit references
Walker, G.W. and MacLeod, N.S., 1991, Geologic map of Oregon: U.S. Geological Survey, scale 1:500,000.
Greene, R.C., Walker, G.W., and Corcoran, R.E., 1972, Geologic map of the Burns quadrangle, Oregon: U.S. Geological Survey Miscellaneous Geologic Investigations Map I-680, scale 1:250,000.
Walker, G.W. and Repenning, C.A., 1965, Geologic map of Adel quadrangle, Lake, Harney, and Malheur Counties, Oregon: U.S. Geological Survey Miscellaneous Geologic Investigations Map I-446, scale 1:250,000.
Brown, C.E. and Thayer, T.P., 1966, Geologic map of the Canyon City quadrangle, northeastern Oregon: U.S. Geological Survey Miscellaneous Geologic Investigations Map I-447, scale 1:250,000.
Prostka, H.J., 1962, Geology of the Sparta quadrangle, Oregon: Oregon Department of Geology and Mineral Industries Geologic Map Series GMS-1, scale 1:62,500.
Brooks, H.C., McIntyre, J.R., and Walker, G.W., 1976, Geology of the Oregon part of the Baker 1o by 2o quadrangle: Oregon Department of Geology and Mineral Industries Geologic Map Series GMS-7, scale 1:250,000.
Walker, G.W., 1979, Reconnaissance geologic map of the Oregon part of the Grangeville quadrangle, Baker, Union, Umatilla, and Wallowa Counties, Oregon: U.S. Geological Survey Miscellaneous Geologic Investigations Map I-1116, scale 1;250,000
Walker, G.W., 1977, Geologic map of Oregon east of the 121st meridian: U.S. Geological Survey Miscellaneous Geologic Investigations Map I-902, scale 1:500,000.
Brooks, H.C., 1979, Geologic map of the Huntington and part of the Olds Ferry quadrangles, Baker and Mlheur Counties, Oregon: Oregon Department of Geology and Mineral Industries Geologic Map Series, GMS-13, scale 1:62,500.
Wolff, E.N., 1965, The geology of the northern half of the Caviness quadrangle, Oregon: Eugene, University of Oregon, Ph.D. dissertation, 214 p.
Brooks, H.C., 2006, Preliminary geologic map of the Mormon Basin quadrangle, Baker County, Oregon: Oregon Department of Geology and Mineral Industries Open-File Map O-06-25, scale 1:24,000.
Ferns, M.L., Brooks, H.C., and Avery, D.G., 1983, Geology and gold deposits map of the Greenhorn quadrangle, Baker and Grant Counties, Oregon: Oregon Department of Geology and Mineral Industries Geologic Map Series GMS-28, scale 1:24,000.
Evans, J.G., Geologic map of the Dooley Mountain quadrangle, Baker County, Oregon: U.S. Geological Survey Geological Quadrangle GQ-1694, scale 1: 24,000.
Brooks, H.C., Ferns, M.L., and Avery, D.G., 1984, Geology and gold deposits of the southwest quarter of the Bates quadrangle, Grant County, Oregon: Oregon Department of Geology and Mineral Industries Geological Map Series GMS-35, scale 1:24,000.
Ferns, M.L., Brooks, H.C., and Wheeler, G.R., 1984, Geology and gold deposits of the Bates quadrangle, Grant County, Oregon: Oregon Department of Geology and Mineral Industries Geological Map Series GMS-31, scale 1:24,000.
Brooks, H.C., Ferns, M.L., Wheeler, G.R., and Avery, D.G., 1983, Geology and gold deposits map of the northeast quarter of the Bates quadrangle, Baker and Grant Counties, Oregon: Oregon Department of Geology and Mineral Industries Geological Map Series GMS-29, scale 1:24,000
Swisher, C.C., Ach, J.A., and Hart, W.K., 1990, Laser fusion 40Ar/39Ar dating of the type Steens Mountain Basalt, southeastern Oregon, and the age of the Steens aeromagnetic polarity transition [abs.]: EOS, Transactions of American Geophysical Union, v. 17, no. 43, p. 1,296.
Brooks, H.C., 1979, Geologic map of the Oregon part of the Mineral quadrangle: Oregon Department of Geology and Mineral Industries Geological Map Series GMS-12, scale 1:62,500.
Brooks, H.C., 1979a, Plate tectonics and the geologic history of the Blue Mountains: Oregon Geology, v. 41, no. 5, p. 71-80.
Brown, M.A., 1996, The pre-Tertiary geology, structural evolution, and geochronology of the Pueblo Mountains, Nevada-Oregon: Houston, Texas, Rice University, master's thesis, 75 p.
Roback, R.C., Vander Meulen, D.B., King, H.D., Plouff, Donald, Munts, S.R., and Willett, S.L., 1987, Mineral resources of the Pueblo Mountains Wilderness Study Area, Harney County, Oregon, and Humboldt County, Nevada: U.S. Geological Survey Bulletin 1740-B, 30 p.
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-1847-C, scale 1:2,500,000, 20 p.
Evans, J.G., 1994, unpub. mapping, Hereford quadrangle, Baker County, Oregon.
Prostka, H.J., 1968, Geologic map of the Ironside 15' quad, Oregon: Oregon Department of Geology and Mineral Industries, scale 1:62,500.
Ferns, M.L., Brooks, H.C., and Avery, D.G., 1983, Geology and gold deposits map of the Greenhorn Quadrangle, Baker and Grant Counties, Oregon: Oregon Department of Geology and Mineral Industries Geological Map Series GMS-28, scale 1:24,000.
Evans, J.G., unpub. mapping, 1994, Ladycomb Peak quadrangle, Harney County
Whitsun, N.W., 1988, Geochemical stratigraphy of the Dooley Rhyolite Breccia and Tertiary basalts in the Dooley Mountain quadrangle, Oregon: Portland, Oregon, Portland State University, master's thesis, 122 p.
Beeson, J.H., Geology of the southern half of the Huntington quadrangle, Oregon: Eugene, University of Oregon, master's thesis, 77 p.
Berry, N.J., 1956, Geology of the northeast quarter of the Huntington quadrangle, Oregon: Eugene, University of Oregon, master's thesis, 78 p.
Weiss, P.L., Gualtieri,, J.L., Cannon, W.F., Tucher, E.T., McMahan, A.B., and Federspiel, F.E., 1976, Mineral resources of the Eagle Cap Wilderness and adjacent areas, Oregon: U.S. Geological Survey Bulletin 1385-E, 100 p.
Counties Baker - Crook - Grant - Harney - Malheur - Union - Wallowa