Silicic vent complexes

Large, rhyolitic to dacitic vent areas in the Cascade Range that commonly include multiple intrusions and much associated silicic eruptive breccia and erosional debris and some flows
State Oregon
Name Silicic vent complexes
Geologic age Miocene
Lithologic constituents
Major
Igneous > Hypabyssal > Felsic-hypabyssal > Hypabyssal-rhyolite (Stock or pipe, Dike or sill)
Igneous > Hypabyssal > Felsic-hypabyssal > Hypabyssal-dacite (Stock or pipe, Dike or sill)
Minor
Igneous > Volcanic > Felsic-volcanic > Rhyolite (Flow, Volcaniclastic-volcanic breccia)
Igneous > Volcanic > Felsic-volcanic > Dacite (Flow, Volcaniclastic-volcanic breccia)
References

Walker, G.W. and MacLeod, N.S., 1991, Geologic map of Oregon: U.S. Geological Survey, scale 1:500,000.

NGMDB product
Counties Deschutes - Douglas - Grant - Hood River - Jackson - Jefferson - Klamath - Lane - Linn - Marion - Wasco