PRELIMINARY BIOCHEMOSTRATIGRAPHY OF THE MULDE INTERVAL (HOMERIAN), WAYNE FORMATION, TENNESSEE, USA

The Mulde Event is a combined extinction event and perturbation to the global carbon cycle that occurred during the Homerian. It is recognized globally and characterized by a double peaked, positive carbon isotope excursion and a mass graptolite extinction. Other paleoenvironmental changes are locally associated with the Mulde Event. For example on Gotland, Sweden, a stepwise conodont extinction coinciding with sequence stratigraphic boundaries occurs before and during the onset of the carbon isotope excursion. The events on Gotland have yet to be observed on a global scale, but preliminary research of the Wayne Formation, TN shows that the eastern midcontinent, USA may also record these events. Three sections near Nashville, TN where potential sequence boundaries are exposed were sampled for petrographic analysis, carbon isotope chemostratigraphy, and conodont biostratigraphy. The Mulde carbon isotope excursion has already been documented in the Wayne Formation, so high-resolution conodont sampling and petrographic analysis of possible sequences boundaries have a high potential to confirm the events recorded on Gotland. The upper Maddox, Waldron, and lower Lego members of the Wayne Formation record the Mulde carbon isotope excursion, and field studies have placed the transgressive systems tract within the upper Maddox Member. This is comparable to the TST within the Bara Oolite Member of the Halla Formation on Gotland.