Carolina Bays on the Eastern Shore of Maryland: II. Distribution and Origin
1987
Stolt, M. H. | Rabenhorst, M. C.
From observations of infrared and black and white aerial photographs, 1500 to 2500 Carolina bays were estimated to occur on the northern Delmarva Peninsula. The bays were found concentrated at elevations between 12 and 24 m above sea level. Two types of depressions were differentiated by the presence or absence of substantial amounts of silty sediments termed basin fill. Slightly more than half of the bays examined contained the basin fill. The basin fill is thought to be loess that has eroded from the catchment area into the closed basins. The loess probably came from the glacially influenced Chesapeake and Delaware Bays. Buried organic-rich horizons were found under the rims of 25% of the bays examined. Carbon-14 dates of 20840 ± 200, and 16280 ± 280 years before present were obtained from two such horizons. It was concluded that bays on the Delmarva Peninsula began forming at about this time period. Depressions are presumed to have originated as wetspots in interdunal areas or as blowouts in sandy barren areas. These depressions could later have gained their shapes, orientation, and sandy rims from depositional and erosional processes generated by wind and waves.
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