The argument that it is difficult to maintain the integrity and 

 identity of a relatively low relief (maximum 18 meters) sand body through 

 a slow transgression of the surf zone across that body applies to Holocene 

 barriers as well as to Pleistocene landf orms . The often-noted occurrence 

 of peat outcrops and tree stumps on the lower foreshore of many Atlantic 

 coast barrier islands indicates that barrier sands once laid seaward and 

 over these lagoonal or back-barrier deposits and have since been stripped 

 off. Field (1974) reviewed the evidence for preservation of relict bar- 

 rier deposits on the shelf and found that very little undisputable evi- 

 dence existed. Although subtle indications of stillstands have been 

 noted by some workers, no actual drowned barrier islands have been posi- 

 tively identified. 



The lithostratigraphic character of the shelf in the vicinity of 

 shoals provides no strong evidence for or against a drowned barrier 

 island origin of shoals. The sequence of medium, well-sorted sands 

 unconformably overlying lagoonal-estuarine muds is characteristic of 

 both barriers and shoals. However, shallow-subsurface sediments of Ocean 

 City and Assateague Island document the tendency for barrier island depos- 

 its not to be preserved in this area. Cross sections along and normal to 

 the barrier (Field, 1976) show that barrier sands are not continuous units 

 and are abruptly reworked in the shoreface area. If shoals mark former 

 sites of the barrier island as it retreated or was overstepped during the 

 Holocene transgression, an intermediate step should be evident. As shown 

 by Field (1976), there is no evidence of such a transition; the barrier 

 is truncated directly seaward of the active beach on the shoreface. 



To briefly summarize, there is a distinct lack of evidence supporting 

 the theory that linear shoals are remnants of overstepped barrier islands. 

 This may be due in part to the fact that some of the criteria either were 

 not examined or are similar to those that support a marine-origin hypothe- 

 sis. Nevertheless, the data gathered in this study are extensive and 

 varied; however, there are no clues to support this hypothesis. It is 

 concluded that overstepping of barrier islands, which may have occurred 

 in isolated situations, is not the principal origin of linear shoals on 

 the inner shelf. The shoals are formed on the seaward side of the barrier , 

 and are therefore a part of the dynamic sediment budget of the barrier, 

 but as the shoreline retreats they become isolated shelf features. 



The most striking characteristic of linear shoals is their abundance 

 and distribution across the shelf from as far as 32 to 48 kilometers (20 

 to 30 miles) offshore to within 1 mile of the beach. Water depths over 

 the crests range from less than 9 meters to more than 30 meters. This 

 wide variation in location and depth suggests that formation was a 

 continuous process, probably associated with sea level rise; it seems 

 unlikely that shoals could have been formed only during a particular time 

 or by a single event. 



The marked similarity between all shoals in all major characteristics 

 (shape, orientation, surface configuration, location with respect to 

 coastal morphology, and internal structure and subsurface sediment rela- 

 tionships) strongly supports a single mode of formation for all shoals. 



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