White (1966) believes capes are merely the present stage of a long temporal 

 sequence of capes . He feels the capes are self maintaining because of 

 continuous emergence of off-cape shoals during emergence of the Coastal Plain. 

 During rising sea level, relict capes formed by major rivers localized younger 

 capes. Present capes, while modified by local conditions, are the present 

 stage in sequences of capes that endured through long periods of sea level 

 change and shoreline migration. 

 Barrier islands and tidal inlets 



38. The third geomorphic zone of Brown (1977) is a 160-km-long stretch 

 of barrier islands and tidal inlets extending from Bull Bay south to the South 

 Carolina-Georgia border. This zone is characterized by barriers averaging 



7 km in length, separated from the mainland by a zone of salt marsh that 

 increases in width southward. Beach face slopes are gentle (1.5 to 2.5 deg) , 

 and sediment is finer (average = 0.143 mm) and better sorted than beaches to 

 the north (Brown 1977) . Greater textural maturity of these sediment indicates 

 their reworking and implies limited new sources of sediment. Offshore slopes 

 are gentle, but irregular spatially depending on their mode of origin; mid- 

 barrier offshore profiles differ considerably from inlet offshore profiles. 



39. Brown recognized two predominant types of barriers occurring within 

 this zone. Transgress ive barriers, generally less than 6 km long, are charac- 

 terized by having a thin pocket of sand overlying back barrier sediments. 

 These rapidly retreating barriers have wide washover terraces, no dunes, nar- 

 row beaches, and straight shorelines. Morris Island, Edingsville Beach, and 

 Bay Point are examples of transgressive barriers. The transgressive nature of 

 these barriers is due in large part to reduction in sediment supply. Wagener 

 (1970) measured over 275 m of retreat for Morris Island between 1949 and 1964 

 as a result of sediment starvation downdrift of the Charleston jetties. 



40. Regressive barriers, also called beach-ridge barriers, are the most 

 common in South Carolina (Brown 1977) . They are characterized by a bulbous 

 updrift (northern) end, a straight to crescentic central portion, and down- 

 drift recurved spits. These barriers are generally unstable at the north 

 ends, prograding at the downdrift end, and stable or slightly accretional in 

 their central portions (Hubbard et al . 1977). They generally exceed 6 km in 

 length and have numerous vegetated beach ridges. 



41. Kiawah Island is an example of a beach- ridge barrier that has been 

 extensively studied. Hayes et al. (1975) recognized the prograding nature of 



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