Geology and Coal Resources of the Centralia-Chehalis District, Lewis and Thurston Counties, Washington

Foraminifera from the Northern Olympic Peninsula, Washington

“…Twin River assemblages that are assigned to the Refugian stage are comparable with Refugian assemblages from the lower and middle part of the Lincoln formation of Weaver (1912) in southwest Washington, where they are referred to the Sigmomorphina schencki and Eponides kleinpelli zones (Rau, 1958).…”

“…P. jenkinsi zone or the Uvigerina cf. U. yazooensis zone (Rau, 1958). In western Oregon similar assemblages are known from the Coaledo formation (Cushman, Stewart, and Stewart, 1947, p. 57-69) and from a lower part of the Toledo formation (Cushman, Stewart, and Stewart, 1949), and they have been observed by the writer from parts of the Nestucca formation.…”

“…Although it is uncommon in the mapped area, it is useful when present because it indicates a late Eocene age in western Washington. It is known from the Cowlitz formation , the Skookumchcuk formation, and the upper part of the McIntosh formation of southwestern Washington (Rau, 1958). It occurs in the lower part of the Twin River formation in the northern Olympic Peninsula.…”

“…This statement is substantiated by observations of the writer in Oregon and in southwestern Washington. In southwestern Washington it makes its lowest occurrence in the Epistominella parva zone (Rau, 1958), which occurs largely in strata mapped as the lower part of the Astoria( ?) formation (Snavely and others, 1958;Pease and Hoover, 1957).…”

“…inflata zone (Rau, 1958), the upper part of the Toledo formation of western Oregon, and the upper part of the San Lorenzo formation of California (Cushman and Hobson, 1935). The Zemorrian stage is generally regarded as "Oligo-Miocene" in age.…”