Inlets are important coastal features for private and commercial 

 water traffic because they are often the only means of access from main- 

 land areas to the ocean. Consequently, bar migrations and shoaling rates 

 must be closely monitored by coastal engineers so that appropriate mainte- 

 nance dredging measures can be planned to maintain the inlet channels in 

 navigable condition. 



Inlet bars are visible around Carolina Beach and Masonboro Inlets 

 (ERTS 1007-15142, Fig. 6). These bars are most striking in bands 4 and 

 5, and barely visible in band 6. Southbound littoral drift at Masonboro 

 Inlet is controlled by a weir jetty at the mouth of the inlet on the north 

 side which results in the ocean bar being a different geometry and posi- 

 tion from the one at Carolina Beach Inlet. The ocean bar at Masonboro 

 Inlet is roughly linear in form and displaced toward the south of the 

 inlet channel which is bordered on the north side by the jetty. The bar 

 trends southeast, approximately parallel to the channel and jetty, and is 

 separated from Masonboro Beach by what is apparently a secondary tidal 

 channel. 



4. Capes . 



Capes Fear and Lookout each have a southeast-trending bar extending 

 from their tips. These bars are seen best in spectral bands 4 and 5. 

 The bar off Cape Lookout is the longer of the two, measuring about 4 

 miles (Fig. 7). The bar off Cape Fear measures 1 mile (Fig. 3). 



Historical records have shown these two capes as sites of shifting 

 current directions (Shepard and Wanless, 1971). Sediment transported 

 toward the tip of each cape by longshore currents is deposited in the 

 shoaling areas as the sediment -laden waters reach the tip. Diffraction 

 around the tip causes waves to lose energy which reduces the sediment 

 carrying capacity of those waves. Shifts in longshore current direction 

 probably prevent these shoals from approaching a direction parallel to 

 the current. The shoals visible in the ERTS-1 imagery are oriented in a 

 direction that reflects net deposition by shifting currents. 



Bumpus (1955) points to converging currents as the mechanism for bar 

 formation off the capes of North Carolina. The prevailing southwesterly 

 wind blows parallel to the direction of the coast south of Cape Hatteras. 

 This wind piles up water on the south side of the capes which results in 

 a hydraulic current flowing out over the projecting bars. The current 

 deflects offshore any southward current approaching the cape from the 

 north side. The resulting decrease in current velocity also causes depo- 

 sition of the sediment load, thus providing a source of sediment for the 

 bars. 



VII. MORPHOLOGICAL CHANGES 



Coastal land features continually undergo erosion and accretion due 

 to the constant action of wind, waves, and currents. As a result, the 

 morphology of the land is constantly subject to change. Some of these 



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