Publications

The Tulip Creek Formation in southern Oklahoma contains an abundant and distinctive assemblage of Chitinozoa. This formation belongs to the Simpson Group and was placed in the Black River Stage of the Champlainian Series (Middle Ordovician) by Harris (1957) and retained there by Schramm (1964). Decker and Merritt (1931) described the stratigraphy and physical characteristics of the Simpson Group in Oklahoma, stating that the Tulip Creek Formation is 394 feet thick at the type locality, which is reported here, and consists of a basal sandstone that has been called “Wilcox” in the section north of Springer, Oklahoma. Higher are alternating shales and limestones, and toward the west a number of thin sandstones alternate with the shales. The megascopic invertebrate fauna reported consists of bryozoans, cystids, crinoids, ostracodes, trilobites, and conodonts.