Xxiv INTRODUCTION 



the formations represented in our own State with those of adjacent 

 commonwealths to the north and south of us. In fact, a solution of 

 many of the problems presented can only be gained after taking into 

 consideration the conditions that have controlled throughout the entire 

 area. 



Maryland, with the adjacent States of Delaware and Virginia, em- 

 braces what with propriety has been called the Middle Atlantic Slope, 

 which comprises in its geology and mineral resources much that is 

 typical of the entire Atlantic border region. In many particulars the 

 record here presented is more complete than that afforded by the States 

 farther to the north and south. No portion of the Atlantic border 

 area has been more thoroughly studied since the early days of American 

 geology, and much of the region may be considered as classic ground to 

 the student of that science. 



The present report is confined to a consideration of a part only of 

 the Coastal Plain. This region embraces the eastern portion of Mary- 

 land, crossing the State from north to south in a broad belt of an aver- 

 age width of 75 miles and extending from the ocean border to the head 

 of tide or slightly beyond on the various estuaries and rivers of the 

 region. 



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 

 the other members of the series. It was seen that only by an under- 

 standing of the broad conditions affecting the whole area could the 

 strata of any one formation be properly interpreted. Eecognizing this 

 fact, the writer presents in later pages a brief discussion of the general 

 relations of the strata composing the Coastal Plain in the Middle Atlan- 



