GEOMORPHOLOGY AND STATIGRAPHY OF A NORTHEASTERN SOUTH CAROLINA BARRIER COMPLEX

As part of the South Carolina Sea Grant Consortium-United States Geological Survey Coastal Erosion program, this continuing study examines the architecture and geomorphology of the DeBordieu barrier island complex along the southern portion of the Grand Strand coastline of northeastern South Carolina. To compare historical geomorphic changes to this barrier complex, aerial photographs from 1939, 1957, 1973, 1988, and 1998 were rectified and overlain using ESRI ArcMap 9. To determine the architecture and geologic development of the island, ground penetrating radar transects were collected along the undeveloped southern and northern sections of the island. Based on these geophysical lines, three shore-normal vibracore transects have been established and two deeper rotosonic cores have been collected. Cores from these transects are analyzed for sediment color, grain size, structures and components and selected subsamples for grain size and organic content from loss by ignition. Initial results indicate a complex geomorphology of a shoreline/dune system seaward of a discontinuous ridge and inlet proximal topographic highs. Results from this study will be compared with other previously studied Grand Strand barrier complexes, which may allow for a better understanding of northeastern south Carolina barrier complexes that are located at the transition between the more extensively studied wave-dominated barrier complexes of North Carolina and the mixed-energy barrier complexes of central South Carolina.