Wolf River batholith; 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; Hager Formation; Rhyolite member
Geologic age Middle Proterozoic
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
References
NGMDB product
Counties Forest - Langlade - Marinette - Oconto