THE PHYSIOGRAPHY OF PRINCE 

 GEORGE'S COUNTY 



BY 



BE^^JAMIN L. MILLEK 



Introductory. 



Maryland is divisible into three grand physiographic provinces, 

 each with certain distinguishing characteristics. These provinces 

 are, beginning Avith the most easterly, the Coastal Plain, the Pied- 

 mont Plateau, and the Appalachian Region. 



These three provinces form bands of somewhat varying width that 

 extend in a northeast-southwest direction, roughly parallel to the 

 shore line, from Kew England to the Gulf of ^Mexico. All three are 

 typically represented in Maryland. Garrett, Allegany and Wash- 

 ington counties form a part of the Appalachian Region ; Frederick, 

 Carroll, Montgomery, Howard, and the northern and northwestern 

 portions of Baltimore, Harford and Cecil counties lie within the 

 Piedmont Plateau; while the remaining portion of the State consti- 

 tutes a part of the Coastal Plain province. 



The elevations, the characteristics of the streams, and the lithologic 

 character and structure of the rocks serve as criteria for the separa- 

 tion of these three provinces. In some places, however, there is such 

 a gradation from one to the other that some difficulty is encountered 

 in drawing the exact boundary line. Passing from the coast west- 

 ward, the country rises at first gTadually until the eastern border of 

 the Piedmont Plateau is reached, then more rapidly lo the Blue 

 Ridge which marks the western boundary of the Piedmont Plateau, 

 and finally in the Appalachian Region the summits of the Appala- 

 chian Mountains are reached in the western portion of the State. 

 The streams of the three provinces are essentially different. The 

 estuaries of the Coastal Plain, occupying broad open valleys form a 



