As a result, smaller manmade structures such as roads and buildings 

 are not visible. However, this resolving capability is suitable for 

 observation of gross coastal features and processes. 



In selected cases, distortion of the shoreline was apparent where 

 image scan lines intersected at nearly right angles to the shoreline, 

 imparting a serrated appearance to the shore. This appearance could be 

 interpreted erroneously as a natural cuspate shore by those unfamiliar 

 with the detailed procedure used to obtain and record the imagery. 



Band 7 shows the greatest tonal contrast between land and water because 

 the water penetration is least in this band (comparable to black and white 

 infrared photography). Contrast, in general, decreases in moving from 

 band 7 to band 4. In some band 4 images, it was difficult to distinguish 

 land from water in backshore areas. Although the water depth penetration 

 is greatest in band 4, it is difficult to distinguish shoal areas from 

 land masses because of poor contrast. Shoal areas were most apparent in 

 band 5. 



Clouds caused problems in distinguishing features on the ground and 

 in the water. In most of the images, cloud cover was light; only one 

 filmset was so heavily covered that analysis was impossible (27 January 

 1973, ERTS 1188-15210). In a few isolated cases, care had to be exercised 

 in distinguishing between shoals and cloud shadows. 



The ERTS-1 images are either contact or enlargement photographs of 

 positive imagery (negative prints). As a result, land areas appear dark 

 and water areas lighter. Contact prints of the four spectral bands 

 showing the study area (11 October 1972, ERTS 1080-15203) are presented 

 in Figure 2. The prominent cape is Cape Fear. Photographic coverage of 

 the shoreline extends from just south of Little River Inlet, South 

 Carolina, north to Bear Inlet, North Carolina. Spectral bands 6 and 7 

 clearly show the Cape Fear River and its tributaries; one tributary extends 

 all the way to the northwest corner of the photo. The barrier islands 

 extending north and south of Cape Fear and the inlets separating the 

 barrier islands are also clearly delineated. Scan-line distortion along 

 the barrier islands is apparent in all four spectral bands, e.g. , Masonboro 

 Beach. 



In bands 4 and 5, contrast between land and water decreases and 

 shoaling areas at the mouths of inlets become more apparent. These two 

 bands illustrate the problem of contrast versus depth penetration. The 

 result was that shoals were studied primarily by using band 5. Sediment 

 plumes, visible in bands 4 and 5, -are seen at the mouth of the Cape Fear 

 River and migrating along the seaward edges of the barrier islands, both 

 north and south of Cape Fear. 



Figure 2 illustrates the problem of cloud cover. Cape Fear has a 

 southeast-trending shoal off its tip visible in the lower spectral bands 

 (discussed later). Cloud cover in the southeast corner of Figure 2 

 obscures any evidence of shoaling off Cape Fear. 



12 



