Maryland Geological Survey 105 



THE GEOLOGIC PEOVINCE 



The Maryland Upper Cretaceous formations comprise part of a nearly 

 continuous belt that extends from Maryland northward through Dela- 

 ware and New Jersey to the islands off the New England coast as well 

 as to southern Massachusetts. Although transgressed by Tertiary deposits 

 in Virginia they reappear in surface outcrops in North Carolina where 

 they present somewhat different characters and where the strata have been 

 described under different names. From this area they have been traced 

 southward to the Gulf, where they again take on different characters and 

 have been described under still other names. Even within the north- 

 ern area the strata are in places transgressed by Tertiary or Quaternary 

 deposits, the latter at times covering the Upper Cretaceous beds exten- 

 sively in the interstream areas, while in the extreme northern part of the 

 district the surface continuity of the beds is broken by bays and estuaries. 



Unlike the Lower Cretaceous strata which attain their most complete 

 development in Maryland, the Upper Cretaceous formations of this 

 northern district are best developed in New Jersey, the Maryland deposits 

 representing the gradual thinning out of these formations to the south- 

 ward. It is significant that the Lower Cretaceous formations are over- 

 lapped northward by the Upper Cretaceous and are unknown in the 

 northern part of New Jersey Coastal Plain and in the islands off the 

 New England coast, whereas the transgressions hitherto described within 

 the Upper Cretaceous are developed to the southward with the gradual 

 overlapping of the several formations in that direction. These trans- 

 gressions, within the Upper Cretaceous, however, are not of equal signifi- 

 cance, although clearly defined in each instance. The Monmouth trans- 

 gression is apparently more pronounced than the Magothy and the 

 Matawan, since the Monmouth deposits entirely transgress the Matawan 

 and come to rest on the Magothy in the southern part of the district. 



The most extensive development of the Upper Cretaceous series within 

 the province is to be found in Monmouth County, New Jersey, where each 

 of the formations attains large, if not in each case maximum, thickness 

 and where the differentiation of the deposits and faunas has led to the 



