Rhyolitic intrusive rocks with aphanitic groundmass

Tertiary rhyolitic intrusive rocks also are present in every county of Nevada. They include many rocks mapped as rhyolite or rhyolite porphyry, rhyolite intrusive rocks, rhyolite plugs or flows, microgranite dikes, and many other undifferentiated intrusive rocks.
State Nevada
Name Rhyolitic intrusive rocks with aphanitic groundmass
Geologic age Miocene to middle Eocene
Lithologic constituents
Igneous > Plutonic > Granitic > Granite (Dike or sill)microgranite dikes
Igneous > Plutonicmany other undifferentiated intrusive rocks
Igneous > Hypabyssal > Felsic-hypabyssal > Hypabyssal-rhyolite (Dike or sill, Flow)
NGMDB product
Counties Churchill - Clark - Elko - Esmeralda - Eureka - Humboldt - Lander - Lincoln - Lyon - Mineral - Nye - Pershing - Storey - Washoe - White Pine