LITHOSTRATIGRAPHY AND CONODONT BIOSTRATIGRAPHY OF THE UPPER MISSISSIPPIAN TAHLEQUAH MEMBER, MOOREFIELD FORMATION BASED ON THE TYPE LOCALITY

The Tahlequah Member (Meramecian) is the lowermost unit within the Mayes Group of northeastern Oklahoma as defined by Dr. George Huffman in 1958. The type section is located along Tahlequah Creek in Section 4 of Township 16 North, Range 22 East within the city limits of Tahlequah, Oklahoma. An adjacent exposure was measured, described and sample in detail. The Tahlequah Member overlies the Osagean Keokuk Formation and Short Creek Oolite with apparent unconformity. It is overlain conformably by the Bayou Manard Member of the Mayes Group. The Tahlequah Member is composed of gray, medium to coarse-grained glauconitic limestone and interbedded calcareous shale. Beds within the Tahlequah Member occur as a succession of clinoforms that thicken away from a Keokuk paleotopographic high.

The age of the Tahlequah Limestone has been controversial for some time. Huffman (1958) correlated the Tahlequah Member to the Warsaw Limestone, Meramecian of the Midcontinent. Brenkle and Lane (1974) concluded that the Tahlequah and Bayou Manard members were younger than the Warsaw and of St. Louis age. This was based on the occurrence of unspecified conodonts from the Apatognathus scalensus-Cavusgnathus Zone along with Gnathodus homopunctatus from those units.

The current study from the type area demonstrates conclusively that the Tahlequah Limestone belongs to the Gnathodus texanus-Taphrognathus varians Zone based on the co-occurrence of these two species. These conclusions therefore support correlation of the Tahlequah Limestone with the Warsaw.