Basalt, gravel, and pumice; Late Pleistocene basaltic volcanics and interlayered sedimetnsof subunit 3b; Snake River Plain (IDQpu3b;0)

State	Idaho
Name	Basalt, gravel, and pumice; Late Pleistocene basaltic volcanics and interlayered sedimetnsof subunit 3b; Snake River Plain
Geologic age	Late Pleistocene
Original map label	Qpu3b
Comments	Formational names are mostly from measured sections of intra-canyon flows. Of larger areal distribution are coalescent unnamed low shields, tube flows, ponded flows, fissure flows, and small cinder cones.
Primary rock type	tholeiite
Secondary rock type	lava flow
Other rock types	gravel; pumice
Lithologic constituents	Major Igneous > Volcanic > Mafic-volcanic > Basalt (Flow)tholeiitic pahoehoe, olivine and plag-phyric, and non-phyric Minor Unconsolidated > Coarse-detrital > Gravel (Bed)Crowsnest Gravel Incidental Igneous > Volcanic > Mafic-volcanic > Basalt (Pyroclastic, cinder cone)cinder cones and other pyroclastic deposits
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. Malde, H.E. and Powers, H.A., 1962, Upper Cenozoic stratigraphy of western Snake River Plain, Idaho: Geological Society of America Bulletin, v. 73, no. 10, p. 1197-1220. Malde, H.E., 1982, The Yahoo Clay, a lacustrine unit impounded by the McKinney basalt in the Sanke River Canyon near Bliss, Idaho: in Bonnichsen, Bill, and Breckenridge, R.M., eds., Cenozoic Geology of Idaho: Moscow, Idaho, Idaho Bureau of Mines and Geology Bulletin 26, p. 617-628. Rember, W.C., and Bennett, E.H., 1979, Geologic map of the Dubois quadrangle, Idaho: Moscow, Idaho, Idaho Bureau of Mines and Geology Map Series, Dubois 2o quadrangle, scale 1:250,000. Rember, W.C., and Bennett, E.H., 1979, Geologic map of the Idaho Falls quadrangle, Idaho: Moscow, Idaho, Idaho Bureau of Mines and Geology, Geologic Map Series, Idaho Falls 2o quadrangle, scale 1:250,000. Malde, H.E., 1971, History of the Snake River Canyon indicated by revised stratigraphy of Snake River Group near Hagerman and King Hill, Idaho: in Shorter Contributions to General Geology, 1969: U.S. Geological Survey Professional Paper 644-F, F1-F21. [http://pubs.er.usgs.gov/publication/pp644F] Armstrong, R.L., Leeman, W.P., and Malde, H.E., 1975, K-Ar dating, Quaternary and Neogene volcanic rocks of the Snake River Plain, Idaho: American Journal of Science, v. 275, p. 225-251. Mitchell, V.E.., and Bennett, E.H., 1979, Geologic map of the Ashton quadrangle, Idaho: Moscow, Idaho, Idaho Bureau of Mines and Geology, Geologic Map Series, Ashton 2o Quadrangle, scale 1:250,000. Mitchell, V.E., and Bennett, E.H., 1979, Geologic map of the Driggs quadrangle, Idaho: Moscow, Idaho, Idaho Bureau of Mines and Geology, Geologic Map Series, Driggs 2o Quadrangle, scale 1:250,000. Greeley, Ronald, 1982, The style of basaltic volcanism in the eastern Snake River Plain, Idaho: in Bonnichsen, Bill, and Breckenridge, R.M., eds., Cenozoic Geology of Idaho: Moscow, Idaho, Idaho Bureau of Mines and Geology Bulletin 26, p. 407-421 Leeman, W.P., 1982, Olivine tholeiitic basalts of the Snake River Plain, Idaho: in Bonnichsen, Bill, and Breckenridge, R.M., eds., Cenozoic Geology of Idaho: Moscow, Idaho, Idaho Bureau of Mines and Geology Bulletin 26, p. 181-191.
Geographic coverage	Bingham - Blaine - Bonneville - Butte - Clark - Fremont - Jefferson - Lincoln - Madison - Minidoka - Power