Maryland Geological Survey 67 



Strike, Dip, and Thickness. — The strike of the Matawan formation 

 is in general similar to that of the underlying Magothy formation and 

 continues in a northeast-southwest direction from the Delaware line to 

 northern Prince George's County. The dip of the beds is to the southeast 

 and east at the rate of about 25 feet in the mile. The thickness of the 

 formation in Cecil and Kent counties reaches a maximum of about 70 feet. 

 To the southward it declines gradually in thickness until it reaches an 

 average of about 50 feet in Anne Arundel County. Toward the Patuxent 

 River it gradually thins and finally disappears a few miles to the south- 

 westward, in northern Prince George's County. 



Stratigraphic and Structural Relations. — The Matawan forma- 

 tion rests unconformably on the Magothy formation. No marked irregu- 

 larities occur, but the Matawan formation gradually transgresses the 

 Magothy to the southward as already pointed out. 



The Matawan formation is also unconformably overlain by the Mon- 

 mouth formation. Although no marked irregularities of contact have 

 been observed, the Monmouth formation transgresses the Matawan for- 

 mation to the southward where it finally overlaps it altogether and comes 

 to rest on the Magothy formation. 



The internal stratigraphy and structure of the Matawan is very simple 

 because of the slight variability in the character of the materials over wide 

 areas. The somewhat more arenaceous character of the upper beds is not 

 sufficiently marked, however, to justify the separation of the Matawan 

 into independent members, especially as no faunal differences are recog- 

 nizable either in Maryland or to the northward in New Jersey. 



Organic Remains. — The Matawan deposits in Maryland have fur- 

 nished only animal remains, with the exception of a single cone scale of 

 Dammara from Millersville, Anne Arundel County. The animal remains 

 are entirely of marine types and probably lived under conditions of 

 moderate depth, such as are found well within the 100-fathom line. 

 Among the groups represented are Echinodermata, Vermes, Bryozoa, 

 Crustacea, Pelecypoda, Gastropoda, Cephalopoda, and Pisces. The fossils 

 have been found chiefly in the dark-colored sandy clays. 



