MARYLAND GEOLOGICAL SURVEY Ixvii 



state from Delaware a few miles south of Galena, and after crossing 

 it from northeast to southwest continue on into Virginia. On the 

 Eastern Shore the Miocene formations are found in Kent county, 

 throughout a larger portion of Queen Anne's, Talbot, Caroline and a 

 part of Dorchester counties, and on the Western Shore in southern 

 Anne Arundel, most of Prince George's, a large part of Charles and 

 almost the entire extent of Calvert and St. Mary's counties. Within 

 the limits of Maryland the Miocene beds dip gently to the southeast 

 and usually, where the contact has been seen, are found to lie on the 

 eroded surface of the Eocene beds. Near Good Hope, however, and at 

 Soldiers' Home, in the District of Columbia, the underlying forma- 

 tion belongs to the Potomac Group. 



As the Miocene beds lie Avholly within the tide-water region of 

 Maryland, the streams which drain the territory are tidal estuaries 

 throughout much of their courses and consequently are slow and slug- 

 gish. On the Eastern Shore we have the Chester and Choptank rivers 

 and their trilnitaries, together with streams emptying into Eastern 

 Bay; and on the Western Shore, the Patuxent and the Potomac and 

 the tributaries which enter the latter below Washington. Throughout 

 much of the area under discussion the country is low and featureless, 

 seldom rising in the eastern counties to 80 feet in elevation. On the 

 Western Shore, however, the surface is more rolling, and the general 

 elevation of the higher portion amounts in certain instances to as much 

 as 300 feet. 



Southern Maryland is most favorably situated of all the districts in 

 the northern portion of the Atlantic Coast province for the study of 

 the Miocene formations. Within the borders of this district many of 

 the features which are wanting in other regions find their full develop- 

 ment. The materials composing the Miocene beds, which are ob- 

 scured in some other regions, here differentiate into three well-defined 

 formations, and the organic remains so indispensable to the geologist, 

 while absent in some deposits in other regions, are in Maryland found 

 in great beds many feet in thickness and miles in extent. In other 

 localities the exploration of these deposits is greatly retarded through 

 lack of exposures, but in this State we have, in the famous Calvert 



