302 THE GEOLOGY OF CALVERT COUNTY > 



wave-built terrace composed of clay, loam, peat, sand, gravel, and ice- 

 borne boulders, which have been deposited by the waves of Chesapeake 

 Bay and its estuaries. The surface of the Talbot formation is coinci- 

 dent with the lowest of the terrace surfaces described above. Since its 

 deposition it has suffered less from erosion than either the Sunderland 

 or Wicomico formations. 



Areal Distribution. 



The Talbot formation is developed as a fringe about the margin of the 

 Wicomico and occupies the lowest level of the three terraces. In the 

 valley of the Patuxent Eiver, as well in the depressions of its principal 

 tributaries, the Talbot formation is found well developed, but on the 

 Bay shore it seems to have suffered considerably from erosion and is 

 absent along much of the coast line. It may be seen, however, near 

 Chesapeake Beach, Dares Wharf, Cove Point, and Drum Point. In these 

 localities it seems to have been deposited near the headwaters of former 

 valleys, the lower portions of which have been removed by erosion. 



A large number of streams have started to sink gullies in the body of 

 the Talbot formation, but as yet have not developed extensive drainage 

 systems and the continuity of the deposit has been, therefore, little 

 affected by them. 



Structure and Tliic'kness. 



The base of the Talbot formation ranges in elevation from a few feet 

 above, to a few feet below tide. There seems to be no general rule for 

 this variation and it is apparently due to deposition on a slightly uneven 

 surface. The highest portions of the surface of the Talbot formation 

 are found around the margin where it abuts against the Wicomico for- 

 mation. Here at the base of the Talbot-Wicomico scarp it has an alti- 

 tude of about 40 to 45 feet and slopes away gently toward the surround- 

 ing waters. This is not to be attributed to a tilting of the formation, 

 but is due to the original attitude which the formation had when it was 

 deposited. 



The thickness of the Talbot formation is variable. Kear Dares Wharf 



