High Resolution Conodont Biostratigraphy of Osagean (upper Tournaisian and early Visean) Strata of North America
Darwin Boardman, Thomas Thompson, Cory Godwin, Sal Mazzullo, and Brian Willhite
A refined biostratigraphic model is necessary in delineating the spatial and temporal distribution of the wide diversity of Mississippian reservoirs within the Midcontinent (including detrital chert, tripolite, spiculites, mounds, dolomitized reservoirs and fractured reservoirs). Additionally, the sedimentary dynamics of the Lower Mississippian diachronous prograding carbonate wedges are documented using biostratigraphically constrained time lines . Evidence is also presented for Early Mississippian tectonics with missing sections delineated by biostratigraphically significant time lines. A new conodont-based conodont zonation is herein proposed for the Osagean Stage. The top of the Kinderhookian Stage is characterized by the cooperi-haasi –punctatus Zone. The base of the Osagean Stage is denoted by the communis carina –punctatus Zone which is defined by appearance of Polygnathus communis carina along with the continued appearance of upper Gnathodus punctatus. In ascending order this zone is followed by the lower multistriatus Zone, upper multistriatus Zone anchoralis-latus Zone, distortus lanei Zone, mehli Zone, bulbosus Zone, lower texanus Zone, and the upper texanus –linguiformis Zone. The base of the Meramecian Zone is defined by a new species of Gnathodus (G, aff. punctatus) that occurs with representatives of the Gnathodus texanus fauna. This new zonation is based on collections from long stratigraphic sections exposed at Roaring River State Park, Missouri and a new roadcut at Jane, Missouri that exposed all zones to and including he lower texanus Zone. The upper texanus-linguiformis Zone and lower Meramacean Gnathodus aff. punctatus zones are represented by smaller sections in the Joplin, Missouri area and in the Wyandotte, Oklahoma area.
AAPG Search and Discovery Article #90176©AAPG Mid-Continent Meeting, Wichita, Kansas, October 12-15, 2013