STRATIGRAPHY OF THE LATE PLEISTOCENE MYRTLE BEACH (SOUTH CAROLINA) BARRIER ISLAND SYSTEM

The Myrtle Beach, South Carolina region is currently a mixed-energy, mainland-attached barrier system. A series of Pleistocene barrier islands rises from sea level to approximately 9 m within 500 m of the modern coastline. This study investigates the stratigraphy of two emergent barrier system composed of three barrier ridges, centering in an area around the downtown Myrtle Beach, SC, area. Vibracores and approximately 25 trackline-km of ground penetrating radar data have been used to describe the internal geometry of these emergent barrier island complexes. Radarfacies reveal ancient shoreface geometries that tie with topographic relief as well as cut and fill sequences through the barrier system. Although the exact age of this barrier system is unknown, the relative position along the coast line combined with former studies indicate that these surficial deposits are younger than oxygen isotope Stage 9 and older than late Stage 5. Future studies of this Coastal Carolina University – NSF funded project will expand to the south and north along the Grand Strand in Long Bay to further delineate the geometry and relative ages of these emergent marine terraces.