Basaltic andesite and basalt

Flows and flow breccia dominantly of basaltic andesite containing plagioclase, olivine, and pyroxene phenocrysts and olivine-bearing basalt representing part of the volcanic sequence of the High Cascade Range (Thayer, 1937). Unit mostly forms small shield volcanoes, gentle-sided lava cones, and, in places, intracanyon flows
State Oregon
Name Basaltic andesite and basalt
Geologic age Quaternary
Lithologic constituents
Major
Igneous > Volcanic > Mafic-volcanic > Basalt (Flow)
Igneous > Volcanic > Mafic-volcanic > Basaltic-andesite (Flow)
Comments smaller cones and flows
References

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

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