barrier is such a coast. It is a convex (bowed seaward), barrier spit 

 interrupted by only one inlet at Ocean City (Fig. 9). Fathometer tran- 

 sects were made across selected shoals in the region in 1974 and profiles 

 were constructed by direct tracing of f athograms . Perturbations in the 

 records caused by wave motion of the boat were smoothed out . 



Profiles of Little Gull and Great Gull Banks, two shoals lying off- 

 shore of Ocean City Inlet in an en echelon configuration (parallel but 

 offset to the southeast) with Ocean City shoal, are shown in Figure 10. 

 Both shoals are similar in cross section and display certain distinct 

 trends in shape that may yield some information on how they evolved or 

 are evolving. The shoals, relatively narrow and single-crested on their 

 southern ends, gradually become broader and multicrested toward the 

 northern ends. Width increases by a factor of 1.5 to 5. The crest shape 

 of Little Gull Banks changes progressively from single-crested (line N) 

 to bicrested (line Q) to tricrested (line P) to an irregular multicrested 

 shape (line 0) (Fig. 10). The initial subdivision of the crest of Great 

 Gull Banks (Fig. 10) appears as a "furrow" or slight depression (lines L 

 and M) as was noted along the northern end of the Ocean City shoal. Both 

 of these shoals are larger and better defined as a single feature than 

 either the collection of ridges composing Ocean City shoal or the rela- 

 tively small shoreface shoal just south of Ocean City Inlet. 



By comparing the surface configuration of shoals along the shoreface 

 with those just offshore and those lying farther offshore, Field (1976) 

 observed a changing pattern in symmetry, slope, and shape. He noted 

 several possible explanations for the different patterns. Differences 

 in crest shape and side-slopes are significant, indicating either com- 

 pletely different modes of formation or alternately different evolution- 

 ary patterns of features initially formed in a similar fashion. Field 

 (1976) concluded that the "furrows" on nearshore shoals, such as Little 

 Gull and Great Gull Banks, are inherited from a previous evolutionary 

 stage and are in the process of being degraded or smoothed over. 



5. Northern Virginia Inner Shelf . 



The coast of northern Virginia marks the transition between the 

 convex barrier spit (Ocean City-Assateague) to the concave barrier island 

 chain (Wallops Island and south) as shown in Figure 11. The inner shelf 

 also demonstrates a marked change in configuration in the vicinity of 

 Chincoteague. The dominant ridge and swale topography changes abruptly 

 nearshore and more transitional offshore, to a subdued topography. An 

 extensive area of smooth, gently dipping or "flat" bottom lies adjacent 

 to Wallops Island in the lee of Assateague Island. The surface slopes 

 southeasterly at about 0.6 meter per kilometer (4 feet per nautical mile): 

 within the 12- to 15-meter (40 to 50 feet) depth area the slope is only 

 0.4 meter per kilometer (2.5 feet per nautical mile). This contrasts 

 sharply with the local slopes of 12.2 meters per nautical mile common on 

 the flanks of shoals north of Chincoteague. Seaward of the 16-kilometer- 

 wide (10 miles) "level bottom area," the sea floor retains the northeast- 

 southwest orientation common to the linear-shoal field farther north, but 



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