|Name||Subaqueous pyroclastic ejecta of basaltic cinder cones|
|Geologic age||Miocene to Early Pliocene|
Igneous > Volcanic > Mafic-volcanic > Basaltic-andesite (Pyroclastic)
Igneous > Volcanic > Mafic-volcanic > Basalt (Pyroclastic-cinder cone)Also contains material of intermediate composition (basaltic andesite and (or) andesite
Sedimentary > Clastic > Mixed-clastic > Sandstone-mudstone (Bed)
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.
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.
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.
Beeson, J.H., Geology of the southern half of the Huntington quadrangle, Oregon: Eugene, University of Oregon, master's thesis, 77 p.
|Counties||Baker - Crook - Harney - Klamath - Lake - Linn - Malheur|