GASTROPODS OF THE COWLITZ FORMATION

A wee block with Eocene marine gastropods from the Coal Creek, Cowlitz Formation just south of Porter near Longview, WA. 

This beautiful site located in a picturesque ravine behind the Jehovah Witness Hall with large maple trees and a slow-moving river boasts wonderful cockles, gastropods & bivalves. 

One sunny afternoon, I took a nap on the bank of that river and was met with the smell of peppery spiciness. Holy Basil had been planted and spread into a wonderful carpet of purple and green aromatic leaves and flowers.

The Cowlitz Formation outcrops hold fossils dating back to the Paleogene. These fossils were discovered in 1911 through the work of Charles E. Weaver, Charles R. Fettkc, Donald Ross, T. A. Bonser, and Olaf Stromme in their work to study the palaeontology of Western Washington. 

Along with the Cowlitz Formation, they also closely observed the Tejon Formation. These two formations are a part of a greater Eocene of Western Washington. The basaltic lavas and tuffs occurring within the Eocene of western Washington have a thickness ranging from fifteen hundred to two thousand feet.

The Cowlitz Formation is located in the canyon of Olequa Creek between the towns of Winlock and Olequa, in southwestern Lewis County, just northwestern Cowlitz County in Washington State.

The rocks composing this formation are sandstones, shales, conglomerates and a subordinate amount of shaly limestone, together with numerous intercalated layers of tuff and basaltic lava. They are partly marine and partly brackish water deposits. As well as the lovely gastropods you see here, there are some very showy bivalves larger than you can wrap your hand around. Tis a worthy site for collecting.