Mafic vent deposits

Mostly in small stratovolcanoes or shield volcanoes and lava cones of basalt and andesite. Includes agglomerate, breccia, scoria, cinders, ash, restricted flows, and small basaltic intrusive bodies. Transitional into pyroclastic rocks of cinder cones (QTp). May also include rocks of late Miocene(?) age
State Oregon
Name Mafic vent deposits
Geologic age Miocene to Pleistocene
Lithologic constituents
Major
Igneous > Volcanic > Mafic-volcanic > Basalt (Flow, Stock or pipe, Volcaniclastic)
Igneous > Volcanic > Mafic-volcanic > Andesite (Flow, Stock or pipe, Volcaniclastic)
References

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

Greene, R.C., Walker, G.W., and Corcoran, R.E., 1972, Geologic map of the Burns quadrangle, Oregon: U.S. Geological Survey Miscellaneous Geologic Investigations Map I-680, scale 1:250,000.

https://pubs.er.usgs.gov/publication/i680

Ferns, M.L., Brooks, H.C., Evans, J.G., and Cummings, M.L., 1993b, Geologic map of the Vale 30 x 60 minute quadrangle, Malheur County Oregon: Oregon Department of Geology and Mineral Industries Geological Map Series GMS-77, scale 1:100,000.

Walker, G.W., 1977, Geologic map of Oregon east of the 121st meridian: U.S. Geological Survey Miscellaneous Geologic Investigations Map I-902, scale 1:500,000.

https://pubs.er.usgs.gov/publication/i902

Ferns, M.L., 1988, Geology and mineral resources map of the Owyhee Ridge quadrangle. Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Geological Map Series GMS-53, scale 1:24,000.

Ferns, M.L. and Cummings, M.L., 1992, Geology and mineral resources map of The Elbow quadrangle, Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Geological Map Series GMS-62, scale 1:24,000.

Ferns, M.L., 1992, Preliminary geologic map of the Bogus Bench quadrangle, Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Open-File Map O-92-02, scale 1:24,000.

Ferns, M.L., 1992, Preliminary geologic map of the Mustang Butte quadrangle, Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Open-File Map O-92-11, scale 1:24,000.

Ferns, M.L., 1992, Preliminary geologic map of the Sacramento Butte quadrangle, Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Open-File Map O-92-13, scale 1;24,000.

Ferns, M.L., 1992, Preliminary geologic map of the Saddle Butte quadrangle, Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Open-File Map O-92-14, scale 1:24,000.

Ferns, M.L., 1992, Preliminary geologic map of the Wrangle Butte quadrangle, Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Open-File Map O-92-15, scale 1:24,000.

Plumley, P.S., 1986, Volcanic stratigraphy and geochemistry of the Hole in the Ground area, Owyhee Plateau, southeastern Oregon: Moscow, University of Idaho, master's thesis, 161 p.

NGMDB product
Counties Crook - Deschutes - Harney - Jefferson - Klamath - Lake - Malheur - Sherman