Silicic vent rocks (ORTvs;0)

Silicic vent rocks

Plugs and domal complexes of rhyolitic, rhyodacitic, and dacitic composition; includes related near-vent flows, flow breccia, and deposits of obsidian, perlite, and pumice. Locally includes resurgent domes related to caldera complexes. In southeast Oregon many domal complexes younger than 11 Ma exhibit a well-defined southeast to northwest age progression (Walker, 1974; MacLeod and others, 1976) from about 11 Ma to less than 1 Ma

State	Oregon
Name	Silicic vent rocks
Geologic age	Eocene to Pliocene
Lithologic constituents	Major Igneous > Volcanic > Felsic-volcanic > Dacite (Dome, Stock or pipe, Flow) Igneous > Volcanic > Felsic-volcanic > Rhyolite (Dome, Stock or pipe, Flow)
Comments	The rhyolitic domal complexes become younger toward the northwest. Includes volcanics of Westfall Butte (OR148), which contains basalt, and rhyolite of Star Mountain (OR149).
Stratigraphic units	Westfall Butte Volcanics (OR148), Rhyolite of Star Mountain (OR149)
References	Walker, G.W. and MacLeod, N.S., 1991, Geologic map of Oregon: U.S. Geological Survey, scale 1:500,000. Walker, G.W., 1973, Reconnaissance geologic map of the Pendleton quadrangle, Oregon and Washington: U.S. Geological Survey Miscellaneus Geologic Investigations Map I-727, scale 1:250,000. https://pubs.er.usgs.gov/publication/i727 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 Walker, G.W., 1974, Some implications of Late Cenozoic volcanism to geothermal potential in the High Lava Plains of south-central Oregon: The Ore Bin, v. 36, no. 7, p. 109-119. MacLeod, N.S., Walker, G.W., and Mckee, E.H., 1976, Geothermal significance of eastward increase in age of upper Cenozoic domes in southeast Oregon: Second United Nations Symposium on the development and use of geothermal resources, Proseedings, v. 1, p. 465-474. Evans, J.G. and Binger, G.B., 1997, Geologic map of the Westfall Butte quadrangle, Malheur County, Oregon: U.S. Geological Survey Open-File Report 97-481, scale 1:24,000. https://pubs.er.usgs.gov/publication/ofr97481 Ferns, M.L. and Williams, C.P., 1993b, Preliminary geologic map of the Crowley quadrangle, Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Open-File Map O-93-04, scale 1:24,000. Evans, J.G. and Binger, G.B., 1998, Geologic map of the Little Black Canyon quadrangle, Malheur County, Oregon: U.S. Geological Survey Open-File Report 98-493, scale 1:24,000. https://pubs.er.usgs.gov/publication/ofr98493 Evans, J.G. and Binger, G.B., 1998, Geologic map of the Alder Creek quadrangle, Malheur County, Oregon: U.S. Geological Survey Open-File Report 98-484, scale 1:24,000. https://pubs.er.usgs.gov/publication/ofr98484 Evans, J.G. and Binger, G.B., 1999, Preliminary geologic map of the Skull Springs quadrangle, Malheur County, Oregon: U.S. Geological Survey Open-File Report 99-381, scale 1:24,000. https://pubs.er.usgs.gov/publication/ofr99381 Evans, J.G., 1996, Geologic map of the Monument Peak quadrangle, Malheur County, Oregon: U.S. Geological Survey Miscellaneous Field Studies Map MF-2317, scale 1:24,000. https://pubs.er.usgs.gov/publication/mf2317 Evans, J.G., Rytuba, J.J., Binger, G.B., and Hooper, P.R., 1999, Preliminary geologic map of the Star Creek Reservoir quadrangle, Malheur County, Oregon: U.S. Geological Survey Open-File Report 99-583, scale 1:24,000. https://pubs.er.usgs.gov/publication/ofr99583 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 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. Ferns, M.L. and Williams, C.P., 1993, Preliminary geologic map of the Burnt Flat quadrangle, Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Open-File Map O-93-2, scale 1:24,000. Ferns, M.L. and Williams, C.P., 1993, Preliminary geologic map of the Crowley quadrangle, Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Open-File Map O-93-04, scale 1:24,000. Camp, V.E., Ross, M.E., and Hanson, W.E., 2003, Genesis of flood basalts and Basin and Range volcanic rocks from Steens Mountain to the Malheur River Gorge, Oregon: Geological Society of America Bulletin, v. 115, no. 1, p. 105-128. Johnson, J.A., 1995, Geologic evolution of the Duck Butte eruptive center, High Lava Plains, southeastern Oregon: Corvallis, Oregon State University, master's thesis, 151 p. Johnson, J.A. and Grunder, A.l., 2000, The making of intermediate compositional magma in a bimodal suite: Duck Butte eruptive center, Oregon, USA: Journal of Volcanology and Geothermal Research, v. 95, p. 175-195. Rytuba, J.J., Minor, S.A., Conrad, W.K., and Vander Meulen, D.B., 1982, Geologic map of the Trout Creek Canyon quadrangle, Harney County, Oregon: U.S. Geological Survey Open-File Report 82-281, scale 1:24,000. https://pubs.er.usgs.gov/publication/ofr82281 Rytuba, J.J., Minor, S.A., and Vander Meulen, D.B., 1983, Reconnaissance geologic map of the Whitehorse Ranch quadrangle, Harney and Malheur Counties, Oregon: U.S. Geological Survey Open-File Report 83-0284, scale 1:24,000. https://pubs.er.usgs.gov/publication/ofr83284 Rytuba, J.J., Minor, S.A., and Vander Meulen, D.B., 1983, Geologic map of the Pole Canyon quadrangle, Harney County, Oregon: U.S.Geological Survey Open-File Report 83-0285, scale 1:24,000. Vander Meulen, D.B., Rytuba, J.J., Minor, S.A., and Harwood, C.S., 1989, Preliminary geologic map of the Three Fingers Rock quadrangle, Malheur County, Oregon: U.S. Geological Survey Open-File Report 89-344, scale 1:24,000. https://pubs.er.usgs.gov/publication/ofr89344
NGMDB product	NGMDB product page for 16259
Counties	Crook - Deschutes - Douglas - Harney - Klamath - Lake - Malheur

Silicic vent rocks

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

Walker, G.W., 1973, Reconnaissance geologic map of the Pendleton quadrangle, Oregon and Washington: U.S. Geological Survey Miscellaneus Geologic Investigations Map I-727, scale 1:250,000.

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.

Walker, G.W., 1974, Some implications of Late Cenozoic volcanism to geothermal potential in the High Lava Plains of south-central Oregon: The Ore Bin, v. 36, no. 7, p. 109-119.

MacLeod, N.S., Walker, G.W., and Mckee, E.H., 1976, Geothermal significance of eastward increase in age of upper Cenozoic domes in southeast Oregon: Second United Nations Symposium on the development and use of geothermal resources, Proseedings, v. 1, p. 465-474.

Evans, J.G. and Binger, G.B., 1997, Geologic map of the Westfall Butte quadrangle, Malheur County, Oregon: U.S. Geological Survey Open-File Report 97-481, scale 1:24,000.

Ferns, M.L. and Williams, C.P., 1993b, Preliminary geologic map of the Crowley quadrangle, Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Open-File Map O-93-04, scale 1:24,000.

Evans, J.G. and Binger, G.B., 1998, Geologic map of the Little Black Canyon quadrangle, Malheur County, Oregon: U.S. Geological Survey Open-File Report 98-493, scale 1:24,000.

Evans, J.G. and Binger, G.B., 1998, Geologic map of the Alder Creek quadrangle, Malheur County, Oregon: U.S. Geological Survey Open-File Report 98-484, scale 1:24,000.

Evans, J.G. and Binger, G.B., 1999, Preliminary geologic map of the Skull Springs quadrangle, Malheur County, Oregon: U.S. Geological Survey Open-File Report 99-381, scale 1:24,000.

Evans, J.G., 1996, Geologic map of the Monument Peak quadrangle, Malheur County, Oregon: U.S. Geological Survey Miscellaneous Field Studies Map MF-2317, scale 1:24,000.

Evans, J.G., Rytuba, J.J., Binger, G.B., and Hooper, P.R., 1999, Preliminary geologic map of the Star Creek Reservoir quadrangle, Malheur County, Oregon: U.S. Geological Survey Open-File Report 99-583, 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 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.

Ferns, M.L. and Williams, C.P., 1993, Preliminary geologic map of the Burnt Flat quadrangle, Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Open-File Map O-93-2, scale 1:24,000.

Ferns, M.L. and Williams, C.P., 1993, Preliminary geologic map of the Crowley quadrangle, Malheur County, Oregon: Oregon Department of Geology and Mineral Industries Open-File Map O-93-04, scale 1:24,000.

Camp, V.E., Ross, M.E., and Hanson, W.E., 2003, Genesis of flood basalts and Basin and Range volcanic rocks from Steens Mountain to the Malheur River Gorge, Oregon: Geological Society of America Bulletin, v. 115, no. 1, p. 105-128.

Johnson, J.A., 1995, Geologic evolution of the Duck Butte eruptive center, High Lava Plains, southeastern Oregon: Corvallis, Oregon State University, master's thesis, 151 p.

Johnson, J.A. and Grunder, A.l., 2000, The making of intermediate compositional magma in a bimodal suite: Duck Butte eruptive center, Oregon, USA: Journal of Volcanology and Geothermal Research, v. 95, p. 175-195.

Rytuba, J.J., Minor, S.A., Conrad, W.K., and Vander Meulen, D.B., 1982, Geologic map of the Trout Creek Canyon quadrangle, Harney County, Oregon: U.S. Geological Survey Open-File Report 82-281, scale 1:24,000.

Rytuba, J.J., Minor, S.A., and Vander Meulen, D.B., 1983, Reconnaissance geologic map of the Whitehorse Ranch quadrangle, Harney and Malheur Counties, Oregon: U.S. Geological Survey Open-File Report 83-0284, scale 1:24,000.

Rytuba, J.J., Minor, S.A., and Vander Meulen, D.B., 1983, Geologic map of the Pole Canyon quadrangle, Harney County, Oregon: U.S.Geological Survey Open-File Report 83-0285, scale 1:24,000.

Vander Meulen, D.B., Rytuba, J.J., Minor, S.A., and Harwood, C.S., 1989, Preliminary geologic map of the Three Fingers Rock quadrangle, Malheur County, Oregon: U.S. Geological Survey Open-File Report 89-344, scale 1:24,000.