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Wolf River batholith (1470 Ma); Hager Formation; Rhyolite member

Wolf River batholith (1470 Ma); Hager Formation; Rhyolite member- Gray to reddish-gray, slightly foliated, porphyritic rhyolite containing aligned phenocrysts of alkali feldspar and lesser amounts of plagioclase in a fine-grained matrix of feldspar, biotite, amphibole, and sparse quartz
State Wisconsin
Name Wolf River batholith (1470 Ma); Hager Formation; Rhyolite member
Geologic age Middle Proterozoic
Primary rock type rhyolite
Secondary rock type
Other rock types
Lithologic constituents
Major
Igneous > Volcanic > Felsic-volcanic > RhyoliteGray to reddish-gray, slightly foliated, porphyritic rhyolite containing aligned phenocrysts of alkali feldspar and lesser amounts of plagioclase in a fine-grained matrix of feldspar, biotite, amphibole, and sparse quartz
Map references
Sims, P.K., 1992, Geologic map of Precambrian rocks, southern Lake Superior region, Wisconsin and northern Michigan: U.S. Geological Survey Miscellaneous Investigations Map I-2185, scale= 1:500,000
Unit references
Sims, P.K., 1992, Geologic map of Precambrian rocks, southern Lake Superior region, Wisconsin and northern Michigan: U.S. Geological Survey Miscellaneous Investigations Map I-2185, scale= 1:500,000
Counties Forest - Langlade - Oconto