GRAPHIC CORRELATION OF THE UPPER DEVONIAN IN THE SOUTH-CENTRAL APPALCHIAN BASIN

Previous graphic correlation studies of the Upper Devonian have focused on microfossils as their data sets. There is a lack in correlation studies using macrofossil data sets. This study, uses a high-resolution data set from nine sections consisting of approximately 27, 000 fossils. The data covers an interval from the upper most Givetian to the basal Tournasian and contains the Frasnian and Fammenian extinction boundary. The data set is composed of brachiopods, bivalves, gastropods, Tentaculites and Trilobites that are identified to the species level. Each section is compiled to develop a rough composite standard (CS). Since Shaw in 1964 introduced graphic correlation to the scientific community, various methods have been developed in order to maximize the correlation between two given chronostratigraphic equivalent sections or a database and an intra-chronostratigraphic section. There is the qualitative method in which the biostratigrapher manually picks out the line of correlation (LOC). The other method is the quantative method in which a computer program simulates the best-fit correlation. This study takes the data sets from a local stratigraphic area prepared using both qualitative and quantative methods. Using these two methods to establish a regional correlation of the Upper Devonian. The final outcome is the correlation of all sections in the datasets to establish a local Composite Standard (CS). Then, the local CS can be correlated regionally with other Appalachian macrofossil data sets.