A CROSS SECTION ILLUSTRATING CENOZOIC REALTIONSHIPS FROM THE ORANGEBURG SCARP TO WINYAH BAY, SOUTH CAROLINA

A cross section has been constructed from the Orangeburg Scarp near Fort Motte, SC, through the Middle and Lower Coastal Plains, to Winyah Bay near Georgetown, SC. Information for this cross section was collected from power-auger samples in 10, 7.5-minute quadrangles along the Santee River during STATEMAP mapping and the cross section synthesizes the results. Results include: the identification of 9 Pliocene and Pleistocene Coastal Plain scarps and associated terraces; recognition of the underlying stratigraphy; and the identification of lateral changes in the underlying Paleocene-Oligocene units. The scarps and terraces, and their associated formations, trend subparallel to the modern coastline, have an identifiable set of shoreline and near shoreline facies, are down-stepping (and dip) in a seaward direction. Many of the younger units have removed, or are the product of, reworked older sediments. The spatial distribution of preserved, Oligocene-Paleocene depositional systems varies from west to east and is controlled by either tilting of the Cape Fear Arch, erosional processes, or fault displacement. Ongoing work is refining the understanding of fault controls on the stratigraphy.