valleys of the Chowan River and possibly, of Bennett's, Cole's, 

 Trotman, Catherine and Somerton Creeks, and the small swamps 

 draining into the Dismal. 



The Chowan Sand Ridge is not a part of the Suffolk Scarp. 

 It, however, joins the scarp at Edenton, and is a fluvial 

 counterpart in which several of the higher features correspond 

 with the high stands of the sea which formed the scarp. Some of 

 the steepest portions of the Chowan River Scarp may have been 

 formed by fluvial action some time after the sea receded from the 

 Suffolk Scarp. 



The deposits of the Chowan Sand Ridge are a complex feature, 

 ranging in elevation from near sea level to 47 ft., and in time 

 from recent to 80,000 years ago, and cannot be explained by a 

 single geologic event. Sands of the highest ridge are located 

 in the Gates County Sand Banks, and support the last small stands 

 of longleaf pine and turkey oak in the county. The earliest 

 plausible date for these ridges would be early Sangamon, perhaps 

 80,000 years ago. At this time the area was inundated by the high 

 stand of the sea which deposited the Norfolk Formation to the east 

 of the Suffolk Scarp, and its estuarine counterpart in central 

 Gates County. 



This hypothesis presupposes that the modern course of the 

 Chowan River had already been established during an earlier 

 glacial period, and that these highest deposits were formed perhaps 

 as sand bars and low dunes along the northern edge of the 

 inundated valley. Much of the deposition of sands which were to 

 become the Sand Banks probably occurred during this time. 



Since the highest sands are only about 5 to 15 feet above 

 the interior plateau (Talbot Terrace) , their present configuration 

 could represent estuarine dunes from the mid Sangamon, when sea 

 level had fallen slightly to the upper level of the modern 

 Chowan River Valley. The rest of the lower ridges and flats of the 

 Chowan Sand Ridge are younger features, dating from a series of 

 events in the mid to late Sangamon (perhaps 40,000 to 50,000 years 

 ago. 



After the initial retreat of the sea from its high level in 

 the early Sangamon, there were two separate stillstands in the 

 mid Sangamon, reaching +22 and +26 feet above present sea level 

 respectively (Oaks and DuBar 1974). These corresponded with 

 deposition of the Kempsville and Londonbridge Formations to the 

 east of the Suffolk Scarp. 



The lands on the southern border of the county, between 

 Carter, Trotman and Bennett's Creeks, lie at an elevation of 15 

 to 20 ft. These flats, which were inundated twice during this 

 time, were mantled by sands, either newly deposited or reworked 



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