Lower to middle Paleozoic sequence stratigraphy and paleontology in the greater Louisville, Kentucky, area

The Cincinnati Arch region of Ohio, Kentucky, and Indiana is an icon of North American Paleozoic stratigraphy, as it exposes strata ranging from Ordovician to Pennsylvanian in age. In particular, the highly fossiliferous Ordovician, Silurian, and Middle Devonian successions have been extensively studied since the nineteenth century, and continue to serve as a crucial proving ground for new methods and models of biostratigraphy, chemostratigraphy, and sequence stratigraphy in mixed clastic-carbonate depositional settings. These strata are locally capped by Middle Devonian limestones with their own diverse fauna and unique depositional history. Outcrops near Louisville, Kentucky, provide an excellent opportunity to examine these strata firsthand and discuss sequence stratigraphy, chemostratigraphy, sedimentary envi­ronments, and paleoecology. A series of new roadcuts south of Mount Washington, Kentucky, exposes the lower to middle Richmondian Stage (Upper Ordovician, Cin­cinnatian) and presents a diverse suite of marine facies, from peritidal mudstones to offshore shoals, coral biostromes, and subtidal shales. These exposures are well suited for highlighting the revised sequence stratigraphy of the Cincinnatian Series, presented herein. Nearby outcrops also include much of the local Silurian succes­sion, allowing an in-depth observation of Llandovery and Wenlock strata, includ­ing several chemostratigraphically important intervals that have improved regional and international correlation. Supplementary exposures east and north of Louisville provide context for subjacent and superjacent Ordovician-Silurian strata, as well as examples of lateral facies changes and unconformities. Additionally, the Falls of the Ohio at Clarksville, Indiana, features an exceptional outcrop of the overlying Middle Devonian succession, including an extensive and well-preserved biostrome of corals, sponges, and other marine fauna. These fossil beds, coupled with significant expo­sures in local quarries, are critical for understanding the paleoecology and strati­graphy of the Middle Devonian of the North American midcontinent.