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Rhyolite dikes and plugs; Miocene felsic subvolcanic feeder intrusions; Owyhee Plateau

Tertiary intrusive rock; where adequately dated, intrusions are denoted (Tmi, Tei).
State Idaho
Name Rhyolite dikes and plugs; Miocene felsic subvolcanic feeder intrusions; Owyhee Plateau
Geologic age Tertiary
Comments Tmif (Ti on map ID001 was changed to Tmif to indicate felsic composition. Tmif represents phenocryst-poor rhyolite dikes and plugs (ID112), interpreted as subvolcanic feeders for Miocene volcanic rhyolites of the Silver City Range (16 Ma, ID127).
Primary rock type rhyolite
Secondary rock type
Other rock types
Lithologic constituents
Major
Igneous > Hypabyssal > Felsic-hypabyssal > Hypabyssal-rhyolite (Dike or sill)feeder dikes for rhyolites of the Silver City Range (15.6-16 Ma)
Minor
Igneous > Hypabyssal > Felsic-hypabyssal > Hypabyssal-rhyolite (Stock or pipe)feeder plugs for rhyolites of the Silver City Range (15.6-16 Ma)
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.
Idaho Bureau of Mines and Geology, undated, Geology of the Jordan Valley quadrangle, Oregon-Idaho: Moscow, Idaho, Idaho Bureau of Mines and Geology, scale 1:250,000.
Ekren, E.B., McIntyre, D.H., Bennett, E.H., and Malde, H.E., 1981, Geologic map of Owyhee County, Idaho, west of longitude 116o W.: U.S. Geological Survey Miscellaneous Investigations Series, Map I-1256, 1:125,000 scale.
Counties Owyhee