Subaqueous pyroclastic ejecta of basaltic and andesitic cinder cones (Holocene, Pleistocene, Pliocene, and Miocene?) (ORQTps;0)

Partly consolidated, palagonitized, fine to coarse, scoriaceous altered cinders, bombs, breccia, and minor agglutinate, mostly deposited in subaqueous environment. Commonly with some interlayers and intermixed lacustrine sedimentary rocks. Forms palagonitic tuff and breccia cones and rings (maars) and, in places, palagonitic tuff ridges

State	Oregon
Name	Subaqueous pyroclastic ejecta of basaltic and andesitic cinder cones (Holocene, Pleistocene, Pliocene, and Miocene?)
Geologic age	Miocene to Holocene
Original map label	QTps
Primary rock type	basalt
Secondary rock type	andesite
Other rock types
Lithologic constituents	Major Igneous > Volcanic > Mafic-volcanic > Basalt (Pyroclastic, cinder cone) Minor Igneous > Volcanic > Mafic-volcanic > Andesite (Pyroclastic, cinder cone)
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. [http://pubs.er.usgs.gov/publication/i680] 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. [http://pubs.er.usgs.gov/publication/i902] Ferns, M.L. and Cummings, M.L., 1992, Geology and mineral resources map of The Elbow quadrangle, Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Geological Map Series GMS-62, scale 1:24,000. Ferns, M.L., 1992, Preliminary geologic map of the Jordan Craters South quadrangle, Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Open-File Map O-92-09, scale 1:24,000.
Geographic coverage	Deschutes - Harney - Klamath - Lake