IXX GEOLOGICAL AND PALEONTOLOGICAL RELATIONS 



cut an almost unbroken exposure rising nearly 100 feet in height and 

 extending from Chesapeake Beach to Drum Point, a distance of about 

 30 miles. 



Areal Distribution. 



The Calvert Formation which lies at the base of the Chesapeake Group 

 in Maryland crosses the state from northeast to southwest. On the 

 Eastern Shore it is found in the southeastern corner of Kent county, 

 throughout almost the entire extent of Queen Anne's and the northern 

 portions of Talbot and Caroline counties. Throughout this region the 

 Calvert is so completely buried beneath the loam and sand of the 

 Columbia formations that its boundaries cannot with certainty be estab- 

 lished in all places. Its northern boundar}-, however, appears to enter 

 the state in the southeast corner of Kent county, passes over into Queen 

 Anne's near Crompton, and then continues along the southern bank 

 of Chester river and crosses the southern half of Kent Island to the 

 Bay. The location of the southern boundary of the Calvert formation 

 cannot be definitely fixed, at the present stage of our knowledge. It 

 appears, however, to enter the state near Greensboro and to cross 

 Caroline and Talbot counties as it passes southwest to the mouth of 

 the Choptank river. 



On the Western Shore the Calvert formation is found extensively 

 developed in Anne Arundel, Prince George's, Charles, Calvert and St. 

 Mary's counties. It appears as a long line of outcrop extending from 

 the hills near the head of South river estuary to a place on the Calvert 

 Cliffs near Point of Eocks. With this breadth, it extends across south- 

 ern Maryland from Chesapeake Bay to the Potomac river, and is devel- 

 oped along the latter stream from the hills north of Washington to 

 the mouth of the Wicomico. 



Notwithstanding this great development, the Calvert formation is 

 seldom met with on the surface of the country but must ^ be sought in 

 the cliifs of the larger estuaries and in the walls of stream gorges. 

 As on the Eastern Shore so on the Western, the Calvert formation is 

 covered up by younger formations. Thus, north of a diagonal line 

 running from Herring Bay to Popes Creek, which marks the disappear- 

 ance of the Eocene beds beneath tide level, the Calvert formation rests 

 on the Eocene deposits and is covered up by loam, sand and gravel 



