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Tuffaceous sedimentary rocks and tuffs (lower? Pleistocene or Pliocene)

Rhyolitic to andesitic ash-flow tuffs, pumice-fall deposits, minor mud flows, and older alluvium on the flanks of Newberry volcano (MacLeod and others, 1981; 1982) and in areas west and northwest of Bend
State Oregon
Name Tuffaceous sedimentary rocks and tuffs (lower? Pleistocene or Pliocene)
Geologic age Pliocene to Early Pleistocene
Comments Unit also occurs in eastern Oregon
Primary rock type rhyolite
Secondary rock type andesite
Other rock types pumice
Lithologic constituents
Major
Igneous > Volcanic > Felsic-volcanic > Rhyolite (Pyroclastic, ash-flow)Containsrhyolitic to andesitic ash-flow tuff, pumice fall deposits, minor mudflows,and alluvium on flanks of newberry Volcano
Igneous > Volcanic > Mafic-volcanic > Andesite (Pyroclastic, ash-flow)
Minor
Igneous > Volcanic > Felsic-volcanic > Rhyolite (Pyroclastic, air fall)
Sedimentary > Clastic > Conglomerate (Bed)
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.
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.
Macleod, N.S., Sherrod, D.R., Chitwood, L.A., and McKee, E.H., 1981, Newberry volcano, Oregon, in Johnston, D. A. and Donnelly-Nolan, Julie, eds., Guides to some volcanic terranes in Washington, Idaho, Oregon, and northern California: U.S. Geological Survey Circular 838, 189 p.
Counties Deschutes - Lake