Rau, W. W. (1951). Tertiary foraminifera from the Willapa River Valley of Southwest Washington. Journal of Paleontology. 25: 417-453.
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Rau, W. W.
1951
Tertiary foraminifera from the Willapa River Valley of Southwest Washington
Journal of Paleontology
25: 417-453
Publication
Available for editors
Tertiary sediments more than 5500 feet thick are exposed along a 7-mile portion of the Willapa River Valley in southwest Washington. These strata are varied lithologically but are mostly siltstones and sandstones. They carry numerous Foraminifera of which 81 species belonging in 39 genera of 16 families are discussed and illustrated. These fossils appear to indicate a rather uniform marine environment of an off-shore shallow to intermediate depth. The fauna further suggests slightly warmer conditions than those now existing in bays of the Pacific Northwest. Foraminiferal evidence appears to indicate the presence of at least partial equivalents of the Cowlitz, Keasey-Bastendorf, Lincoln, Blakeley and Astoria formations. It is therefore probable that the fossiliferous strata under consideration range in age from upper Eocene to lower Miocene.