PHYSIOGRAPHIC RECORD. 221 



upon the land as far as it had during the previous submergence. The waves 

 beat against the shores and in many places cut cliffs in the deposits that had 

 been laid down during the former period and occasionally removed the 

 entire width of the Sunderland terrace. Throughout many portions of the 

 Coastal Plain at the present time these old sea cliffs are still preserved as 

 escarpments, frequently 10 to 15 feet in height and occasionally much 

 higher. During this time perhaps about one-half of the Coastal Plain of 

 Virginia was submerged. The Sunderland deposits were largely destroyed 

 by the advancing waves and redeposited over the floor of the Wicomico sea. 

 Those portions of the Sunderland lying above 90 to 100 feet were not 

 submerged and for the most part were not destroyed. Deposition of 

 materials brought in by the streams from the adjoining land also took place. 



During the Wicomico submergence deposition was effective in destroying 

 a great many of the irregularities which had previously existed as shown by 

 the great depth of the deposits formed in the erosion depressions. Many 

 of the submerged stream channels were entirely silted up, yet the deposits 

 were seldom thick enough to fill entirely the channels and valleys of the 

 largel' streams. Accordingly in the uplift following Wicomico deposition, 

 the major streams reoccupied their former channels with perhaps only 

 slight changes. New streams were also developed and the Wicomico plain 

 was" more or less dissected along the stream courses, the divides being at the 

 same time gradually narrowed. This erosion period was terminated by the 

 Talbot submergence which carried part of the land beneath the sea and 

 again drowned the lower courses of the streams. 



Talbot stage. — Talbot deposition did not take place over as extensive an 

 area as had that of the Wicomico. It was confined to the old valleys and to 

 the low stream divides where the advancing waves destroyed the Wicomico 

 deposits. The sea cliffs were pushed back as far as the waves advanced and 

 now standing as escarpments mark the boundaries of the Talbot sea and the 

 Talbot estuaries. This is the Talbot-Wicomico escarpment previously 

 described. In some places the deposits were so thick in the old stream 

 channels that the streams in succeeding period of elevation and erosion 

 found it easier to excavate new courses. Generally, however, the main 

 streams reoccupied their former channels and renewed their corrasive work 

 which had been interrupted by the Talbot submergence. The Talbot plain 

 has now in many places been rendered quite uneven by recent erosion yet 

 it is less irregular than the remnants of the Lafayette, Sunderland, and 

 Wicomico plains which have been subjected to denudation for a much longer 

 period of time. 



