Tertiary granitic rocks

Granite, quartz monzonite, quartz diorite, granodiorite, and trondhjemite. Includes dacite porphyry and granite breccia near Bumping Lake, Yakima County.
State Washington
Name Tertiary granitic rocks
Geologic age Probably mostly Eocene; ranges from Miocene to Paleocene
Lithologic constituents
Major
Igneous > Plutonic > Granitic > Granite (Batholith, Stock or pipe)Oval Peak Batholith, Okanogan County.
Igneous > Plutonic > Granitic > Granodiorite (Pluton)
Minor
Igneous > Plutonic > Syenitic > Quartz-monzonite (Pluton)
Igneous > Plutonic > Dioritic > Quartz-diorite (Batholith, Dike or sill)
Incidental
Igneous > Plutonic > Dioritic > Diorite (Stock or pipe)
Igneous > Hypabyssal > Felsic-hypabyssal > Hypabyssal-rhyolite (Dike or sill)May include stocks or domes.
Igneous > Plutonic > Granitic > Tonalite (Pluton)Includes trondhjemite.
Igneous > Plutonic > Gabbroic > Gabbro
Igneous > Hypabyssal > Mafic-hypabyssal > Hypabyssal-andesite (Dike or sill)May include domes and stocks.
Igneous > Hypabyssal > Felsic-hypabyssal > Hypabyssal-dacite (Dike or sill)May include domes or stocks.
Comments The intrusive volcanic rocks near Bumping Lake include hypabyssal dacite, rhyolite, and andesite (Walsh and others, 1987).
Stratigraphic units Chilliwack granodiorite and quartz diorite; Golden Horn batholith; Silver Star granodiorite; Snoqualmie granodiorite; Index batholith; Grotto batholith (possibly the same as Snoqualmie); Oval Peak batholith; Fawn Peak stock; Pasayten stock-dike; Monument Peak stock; Castle Peak stock; Lost Peak stock
References

Huntting, M.T., Bennett, W.A.G., Livingston, V.E.Jr., and Moen, W.S., 1961, Geologic Map of Washington: Washington Division of Mines and Geology, scale 1:500,000.

Walsh, T.J., Korosec, M.A., Phillips, W.M., Logan, R.T., Schasse, H.W., 1987, Geologic Map of Washington-Southwest Quadrant: Washington Division of Geology and Earth Resources, Geologic Map GM-34, scale 1:250,000.

Luedke, R.G., Smith, R.L., Russell-Robinson, S.L., 1983, Map showing distribution, composition, and age of late Cenozoic volcanoes and volcanic rocks of the Cascade Range and vicinity, northwestern United States: U. S. Geological Survey Miscellaneous Investigations Series Map I-1507, scale 1:500,000.

Stoffel, K.L., Joseph, N.L., Waggoner, S.Z., Gulick, C.W., Korosec, M.A., Bunning, B.B., 1991, Geologic Map of Washington--Northeast Quadrant: Washington Division of Geology and Earth Resources Geologic Map, GM-39, scale 1:250,000.

Cater, F.W. and Crowder, D.F., 1967, Geologic Map of the Holden Quadrangle, Snohomish and Chelan Counties, Washington: U. S. Geological Survey Geologic Quadrangle Map GQ-646, scale 1:62,500.

Miller, R.B., 1987, Geology of the Twisp River-Chelan Divide Region, North Cascades, Washington: Washington Division of Geology and Earth Resources Open File Report 87-17, 12 p.

Misch, P., 1977, Bedrock Geology of the North Cascades, in Brown, E. H. and Ellis, R. C. (eds.), Geological Excursions in the Pacific Northwest, Geological Society of America 1977 Annual Meeting, Seattle: Western Washington University, p. 1-62.

Foster, R.J., 1960, Tertiary Geology of a Portion of the Central Cascade Mountains, Washington: Geological Society of America Bulletin v. 71, no. 2, p. 99-126.

Barksdale, J.D., 1975, Geology of the Methow Valley, Okanogan County, Washington: Washington Division of Geology and Earth Resources Bulletin no. 48, 72 p.

Tabor, R.W., Frizzell, V.A.,Jr., Booth, D.B., Waitt, R.B., Whetten, J.T., Zartman, R.E., 1993, Geologic Map of the Skykomish River 30- by 60-Minute Quadrangle, Washington: U. S. Geological Survey Miscellaneous Investigations Series Map I-1963, scale 1:100,000.

Tabor, R.W., Engels, J.C., Staatz, M.H., 1968, Quartz Diorite-Quartz Monzonite and Granite Plutons of the Pasayten River Area, Washington--Petrology, Age and Emplacement: U. S. Geological Survey Professional Paper 600-C, p. C45-C52.

Phillips, W.M., 1987, Geologic Map of the Vancouver Quadrangle, Washington and Oregon: Washington Division of Geology and Earth Resources Open File Report 87-10, scale 1:100,000.

NGMDB product
Counties Chelan - Clark - Ferry - King - Kittitas - Lewis - Okanogan - Pierce - Skagit - Skamania - Snohomish - Whatcom - Yakima