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Upper upper Eocene nonmarine and marine rocks

Massive to thin-bedded, feldspathic to arkosic sandstone, siltstone, shale, and carbonaceous shale; becomes mostly marine in the western foothills of Cascade Mountains where coal beds are abundant. Basaltic sandstone and siltstone in northern Olympic Peninsula.
State Washington
Name Upper upper Eocene nonmarine and marine rocks
Geologic age Middle Eocene
Comments WAE1 is sometimes undifferentiated from WAE2 in the literature.
Primary rock type sandstone
Secondary rock type siltstone
Other rock types shale; coal; conglomerate; olistostrome; mafic volcanic rock
Lithologic constituents
Major
Sedimentary > Clastic > Sandstone (Bed)Mostly arkosic to feldspathic sandstone but also includes significant amounts of lithic basaltic and quartzose sandstone and smaller amounts of arenite and graywacke in the northern Olympic peninsula.
Minor
Sedimentary > Clastic > Siltstone (Tuffaceous)
Sedimentary > Clastic > Siltstone (Bed)Includes carbonaceous, micaceous, quartzose, and basaltic siltstone.
Incidental
Sedimentary > Coal > Lignite (Bed)
Sedimentary > Clastic > Conglomerate (Bed)
Sedimentary > Clastic > Mudstone > Shale (Bed)Some is carbonaceous (Snavely and others, 1958).
Sedimentary > Clastic > Mixed-clastic (Olistrostrome)
Igneous > Volcanic > Mafic-volcanicInterbedded lenses of pillow basalts in sedimentary rocks in northern Olympic peninsula (Babcock, 1994). Tukwila Formation includes andesitic flow, breccia, and tuff (Frizzell, 1979).
Map references
Huntting, M. T., Bennett, W. A. G., Livingston, V. E. Jr., Moen, W. S., 1961, Geologic Map of Washington: Washington Division of Mines and Geology, scale 1:500,000.
Unit references
Huntting, M. T., Bennett, W. A. G., Livingston, V. E. Jr., 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.
Babcock, R. S., Suczek, C. A., Engebretson, D. C., 1994, The Cresent "Terrane", Olympic Peninsula and Southern Vancouver Island, in Lasmanis, R. and Cheney, E. S., convenors, Regional Geology of Washington State: Washington Division of Geology and Earth Resources Bulletin 80, p. 141-157.
Snavely, P. D., MacLeod, N. S., Niem, A. R., 1993, Geologic map of the Cape Flattery, Challam Bay, Ozette Lake, and Lake Pleasant Quadrangles, Northwestern Olympic Peninsula, Washington: U. S. Geological Survey Map I-1946, scale 1:48,000.
Wells, R. E., 1989, Geologic Map of the Cape Disappointment-Naselle River Area, Pacific and Wahkiakum Counties, Washington: U. S. Geological Survey Miscellaneous Investigations Series Map I-1832, scale 1:62,500.
Roberts, A. E., 1958, Geology and Coal Resources of the Toledo-Castle Rock District, Cowlitz and Lewis Counties, Washington: U. S. Geological Survey Bulletin 1062, 71 p, 6 pls.
Snavely, P. D., Jr., Brown, R. D., Roberts, A. E., Rau, W. W., 1958, Geology and Coal Resources of the Centralia-Chelalis District, Washington: U. S. Geological Survey Bulletin 1053, 149 p.
Walsh, T. J., 1987, Geologic Map of the Astoria and Ilwaco Quadrangles, Washington and Oregon: Washington Division of Geology and Earth Resources Open File Report 87-2, scale 1:100,000.
Turner, D. L., Frizzell, V. A., Triplehorn, D. M., Naeser, C. W., 1983, Radiometric dating of ash partings in coal of the Eocene Puget Group, Washington: Implications for paleobotanical stages: Geology, v. 11, no. 9, p. 527-531.
Frizzell, V. A., 1979, Petrology and Stratigraphy of Paleogene Nonmarine Sandstones, Cascade Range, Washington: U. S. Geological Survey Open File Report 79-1149, 151 p.
Counties Clallam - Cowlitz - Grays Harbor - Jefferson - King - Lewis - Pacific - Pierce - Thurston - Wahkiakum