39 



have been so intensified here as to bring about a complete overlapping 

 and obscuring of the fluvial by the interfluvial, or of the "high level" 

 by the "low level," as denoted in Maryland. The sands are for the 

 most part loose, unconsolidated and to distinguish between succes- 

 sive depositions, without the aid of such phenomena as terraces or 

 bowlders and other things which help in the interpreting of condi- 

 tions farther north, is almost an impossibility at the present stage of 

 investigation into the problem. 



As to the areal distribution of the Pleistocene in the State, it may 

 in a word be said to be the surficial formation over the entire Coastal 

 Plain of the State. According to J. A. Holmes 1 , the Coastal Plain 

 region of the State is covered almost everywhere with a mantle of 

 loose material — loam, clay and sand, the latter predominating. This 

 covering of sand, extending from the shore back to the inner margin 

 of the Coastal Plain and in places overlapping on the crystalline rocks 

 of the Piedmont Plateau, attains an elevation of 400 to 600 feet, and 

 belongs either to the Lafayette or to the Columbia formation. After 

 briefly describing the occurrences of the Cretaceous, the Eocene and 

 the Lafayette, Holmes says of the Columbia : "Spread out over this 

 deeply and irregularly eroded surface, resting in places on the 

 Lafayette or the Eocene or the Cretaceous, or where all these have 

 been removed, even on the crystalline rocks, lies the mantle of sand 

 and loam known as Columbia." He further says : The topography 

 of this inner margin of the Coastal Plain is as old as the post-Creta- 

 ceous and post-Eocene erosion intervals. The valleys and stream 

 channels formed then were nearly filled during the Lafayette deposi- 

 tion, but were opened up again practically along the same lines dur- 

 ing the post-Lafayette erosion period. The Columbia deposition 

 mantled these hills and valleys with a slight covering only, and 

 erosion since that time has made but little change in the general 

 topography of the country in this marginal section of the Coastal 

 Plain. Farther toward the sea the sand becomes finer and has more 

 loam intermixed with it. Just along the present shore line and back a 

 short distance the Pleistocene is overlaid by the Recent sands, which 

 are coarser. It may be well to add that the very slight deposition 

 formed during the Pleistocene submergence has been in places eroded 

 from the hills and has left the orange-colored sands of the Lafayette 

 exposed. This intermixture of the two formations has given the 

 "sand hills" and "red hills" of the State. In studying the Pleistocene 



1 "Geology of the Sandhill Country of the Carolinas" (Geol. Soc. Amer., 

 Bull., Vol. V, pp. 33-35, 1894). 



