THF EOCENE DEPOSITS OF MARYLAND 



BY 



William Bullock Clark and George Curtis Martin 



IXTRODUCTIOX. 



Maryland, as an important division of the Atlantic border region, 

 comprises in its geology and mineral resources mnch that is typical of 

 the entire province. No discussion of Maryland geology, therefore, can 

 be regarded as complete that does not at the same time take into con- 

 sideration the formations of immediately adjacent states. Much may 

 be learned in this way that will be of advantage in interpreting our own 

 geology, since geological deposits are not limited by political boundaries. 



Maryland, together with Delaware and Virginia, forms what has with 

 propriety been termed the Middle Atlantic Slope, and, as described 

 in the earlier volumes of the Survey, has been divided into the Coastal 

 Plain, the Piedmont Plateau, and the Appalachian Eegion. The pres- 

 ent report is confined to a consideration of only a part of the first of 

 these divisions. 



Much interest has been manifested in the Coastal Plain geology and 

 paleontology of the Middle Atlantic Slope since the early days of geo- 

 logical investigation in this country. Many of the most potent illus- 

 trations of the geologists of the early part of the century were drawn 

 from this region, and although the relations of the deposits were not 

 altogether comprehended, yet the recorded observations show an appre- 

 ciation of many of the more difficult problems involved. Later, as the 

 complicated geological history of the Coastal Plain became better known, 

 it was recognized that, if a full understanding of any single formation 

 was to be gained, it was necessary to study carefully not only its litho- 

 logical and paleontological characteristics but also its relationship to 



