Rhyolite ignimbrites; Middle Pleistocene felsic volcanics of subunit 2f; Yellowstone Plateau (IDQpm2f;0)

State	Idaho
Name	Rhyolite ignimbrites; Middle Pleistocene felsic volcanics of subunit 2f; Yellowstone Plateau
Geologic age	Middle Pleistocene
Original map label	Qpm2f; Qpm?f
Comments	Qpm2f (Mesa Falls Tuff) is brownish gray rhyolitic ash-flow tuff (1.2 Ma, K-Ar sanidine), air-fall pumice and distal ash-flow tuff at type section. Ash-flow tuff has large feldspar phenocrysts. Mesa Falls Tuff was erupted during the second eruptive cycle of the Yellowstone Plateau volcanic field, from the Henry's Lake caldera (ID123).
Primary rock type	rhyolite
Secondary rock type	ignimbrite
Other rock types
Lithologic constituents	Major Igneous > Volcanic > Felsic-volcanic > Rhyolite (Pyroclastic, ash-flow)Meas Falls Tuff, distal ash flow and pumice
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. 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. Christiansen, R.L., and Blank, H.R., Jr., 1972, Volcanic stratigraphy of the Quaternary rhyolite plateau in Yellowstone National Park: in Geology of Yellowstone National Park: U.S. Geological survey Professional Paper 729-B, p. B1-B18.
Geographic coverage	Ada - Fremont