Figure 12. Probable site of a large pre-1585 inlet at Kitty Hawk, 

 N. C. (Inlet was located in the left-central part of the picture 

 (Fisher 1962) . Note the longshore bar as evidenced by breaking 

 waves in the Atlantic Ocean at the right side of the photograph. 

 The Wright Brothers Memorial is located in the left foreground) 



near the beach. The shoreface, or inner part of the continental shelf, has a 

 concave profile; seaward of the shoreface, the continental shelf is planar 

 and dips away from the coast. Because wave form is modified and wave energy 

 is dissipated in shallow water, the width of the continental shelf is a factor 

 in regulating the amount of wave energy which reaches and is expended at the 

 coast. The shelf width to the 180-m (100-fathom) isobath narrows from 126 km 

 east of Cape Henry to 48 km east of Cape Hatteras. 



35. Because of its decreasing width, the slope of the continental shelf 

 increases from north to south. The depth at the base of the steep, concave 

 shoreface also increases in that direction (Figure 13) . The profiles shown 

 in the figure are averages of nine profiles, spaced 1.5 km apart, at each 

 location. An analysis of seismic data from the study area suggests the shore- 

 face may be resting unconformably upon older sediments of the planar and 

 seaward-dipping continental shelf; this implies the concave shoreface is 

 shaped by processes (waves, currents) active today or in the recent past. 



27 



