Laser Altimetry of the Carolina Bays

December 16, 2010

Photographer: Michael Davias
Summary Author: Michael Davias; Jim Foster

Photographs of the elliptical shaped and similarly oriented Carolina bays have been available from the air since the early 1930's. Those early images sparked extensive research into the genesis of the bays, but they revealed only a small part of their unique planforms. Tens of thousands of these tree-filled, wetland depressions are found along the Atlantic seaboard of the southeastern United States. Their origin is unknown; though, they may have formed from the impact of a fragmenting meteor or comet. Digital elevation maps (DEM) created with today's Laser Imaging and Range Detection (LiDAR) systems allow for much improved identification and classification of these shallow depressions. The above shaded DEM covers approximately 230 sq mi (600 sq km), centered on Rex, North Carolina (Robeson County). It was generated with the Global Mapper, Geographic Information Systems (GIS) program using LiDAR data obtained from the United States Geological Survey (USGS). The colors shown are an indication of topographic elevation; from 125 ft (38 m) above mean sea level in the lower right, to 240 ft (73 m) above sea level in upper left. Vertical resolutions of just a few centimeters permit the visualization of the form and extent of the bays’ otherwise imperceptible rims. Rockfish Creek flows along the northern edge. Note that the CSX’s Atlantic Coast Line railroad bisects the area diagonally along a strikingly, straight right-of-way, and Interstate 95 can be detected at right center. Image acquired on October 7, 2010.