Owl Creek (Upper Cretaceous) fossils from Crowleys Ridge, southeastern Missouri

Abstract

The Owl Creek formation, which is typically developed in Tippah County, Miss., is now known to extend northward to the head of the Mississippi Embayment in southeastern Missouri. The formation is represented in Crowleys Ridge in Stoddard and Scott Counties, Mo., by 11 feet or less of weathered, mottled, yellowish-brown and greenish-gray, glauconitic, finely micaceous sand or sandy clay, indurated in part to ferruginous, argillaceous sandstone. In Missouri the formation is unconformably underlain by the McNairy sand (Upper Cretaceous), and is unconformably overlain by the Clayton formation (Paleocene). Fossils, mainly mollusks, are contained in the Owl Creek formation of Missouri in greater or less abundance; they are in the form of internal and external molds only; no shell material has escaped solution and removal by circulating ground waters, but many of the molds are identifiable.