Abstract

Lee (1940) named the Cowley Formation for rocks which he believed were deposited in a basin eroded from Osagian and older rocks in a large area in southcentral Kansas in pre-Meramecian time. The Cowley Formation is mapped by Lee as extending in an east-west belt 15 to 75 miles wide north of the Oklahoma border in southcentral Kansas. Silty and siliceous dolomite, limestones, dolomitic siltstone, and variably large amounts of dark, opaque, microfossiliferous chert and chalcedonic chert characterize the Cowley. Locally non-cherty carbonate rocks make up the Osagean and Meramecian rocks within the area of the Cowley. Lee reported that a concentration of glauconite occurs progressively lower stratigraphically westward in Kansas from the eastern Kansas border in pre-Meramecian rocks.

Cores and acid residues examined in the studies by Thompson (1964) and Goebel (1966) revealed the presence of conodont faunas that indicate the Cowley Formation ranges in age from early Osagian into late Meramecian. A normal sequence of Osagian and Meramecian formations is present in southcentral Kansas. Traces of glauconite and secondary sulfide minerals are present locally in these formations. The term Cowley Formation should be replaced by Cowley Facies.