66 THE PLIOCENE AND PLEISTOCENE DEPOSITS OP MAEYLAND 



and part of the fifth fall within the stibaerial division and the last one 

 principally within the submarine division of the Coastal Plain. All 

 five of the subaerial terraces are found on the Western Shore while only 

 three of them occur on the Eastern Shore. These terraces wrap about 

 each other in concentric arrangement and are developed one above the 

 other in order of their age, the oldest standing topographically highest. 

 (Fig. 2.) 



LAF 







SUNDERLAND 



T?fVj; i\ RECENT 



.— 



- 



— ~- 



~ ' r ~'-~ v :. •*;--!;' .^ V, . - wicomico 



OLDER FORMATIONS 



... - '—"^^^^^^V^C-'-.Vy-^ 7- 7 





~~^~~-*- ~^S:^^s^2'-~:.:A 







Fig. 2. — Diagram showing ideal arrangement of the various terrace forma- 

 tions in the Maryland Coastal Plain. 



The Lafayette Terrace. — The highest of the five terraces is known 

 as the Lafayette. It is best developed in Maryland in the region between 

 the Anacostia, Potomac, and Patuxent rivers as far south as Charlotte 

 Hall (Plate I). In other words, it caps the divide at the northern 

 extension of the St. Mary's-Prince George's peninsula. The surface of 

 this terrace varies considerably in appearance according to position. In 

 the interior where it is removed from the influence of streams, it is as 

 flat and featureless as any portion of the Eastern Shore (Plate IV, 

 Fig. 2), but along the margins where it has been dissected by waterways, 

 they have transformed it into a genth T -rolling country and its true 

 character is obscured. Besides this extensive development of the La- 

 fayette terrace, there are remnants of the same surface distributed along 

 the border of the Piedmont Plateau from the Potomac river northeast- 

 ward through Delaware and Pennsylvania to within a few miles of the 

 Delaware river. There are also a few outliers scattered about the Coastal 

 Plain. Most of these are grouped about the southern margin of the 

 principal area in the vicinity of Charlotte Hall, a few more are found 

 in Anne Arundel county, and a very important cluster occurs on the high 

 lulls of Elk Neck in Cecil county. Beyond the Potomac river this 



