ELIMINATING THE MOSAIC: USING FINE SCALE SEQUENCE STRATIGRAPHIC CORRELATIONS TO DECODE SEDIMENTARY FACIES IN THE CINCINNATIAN, MAYSVILLIAN STAGE

Late Ordovician, Cincinnatian age Strata of the Cincinnati area have a rich history of research, and along with this, a plethora of local stratigraphic terms to reflect minor facies changes, across this region. A long standing perception exists that the Cincinnatian and in particular the Maysvillian stage strata comprise a mosaic of local facies that cannot be subdivided and correlated in detail, with little small-scale cyclicity present. The results of a resent field investigation however, yield that this is not the case. Recent research on the Cincinnati arch over the last decade has focused on the Edenian Stage and has established the Kope Formation as an exemplar of a high-resolution stratigraphic and paleoecological study. Building stratigraphically upward from the older Kope Formation, the present study will establish a high-resolution litho- and cyclostratigraphic framework for the slightly younger Maysvillian Stage Strata.

Strata of the Maysvillian Stage including the Fairview (Calloway Creek) and Grant Lake (Ahslock) formations have been divided into a series of members (e.g. Miamitown, Bellevue, Corryville, and Mt. Auburn) in Ohio, but remain largely undifferentiated elsewhere, or masquerade under a myriad of different local names. This gave rise to the view of a complex mosaic of local facies, despite the fact that members, and submembers, defined allostratigraphically, are recognizable throughout the region. By tracing a series of single time planes, event deposits, faunal epiboles, unique marker beds, and low order cycles across depositional facies, in combination with the use of Magnetic Susceptibility, it is now possible to resolve the Maysvillian strata of the entire Cincinnati Arch region in much greater detail. A detailed cyclostratigraphic framework of the Maysvillian stage has been developed making use of a series of 4^th order depositional cycles, traceable across the region, providing a revised sequence architecture that makes use of previously obscured overarching patterns, facies dislocations, marker beds, and widespread regionally truncated disconformities. This new cyclostratigraphic framework can now act as the basis for future paleontological, evolutionary, climatic, or testable sedimentological studies.