120 



GEOLOGY OF THE NAREAGAE"SETT BASIX 



mainiy to do, the acquisition of secondary characters in the strata is very 

 closely related to the degree of tilting which tliey have undergone. Aside 

 from one or two narrow belts of dynamic metamorphism, accompanied by 

 the development of new minerals, the alteration is generally Hmited to the 

 production of cleavages and joint structures. It is on account of this lesser 

 degree of alteration and the identifiable condition of plant remains that 



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I'm. 6— Map showing distribution of metaiworphosed Carboniferous locks 

 A, Ifarragansett Bay area of maximum metamorphism , B, Wmueconnet aiea , 

 C, Momll's area m J;? orfolk Coanty Basm 



this portion of the field affords the best ground in the Carboniferous basin 

 for determining the succession. 



In the subsequent pages the attempt to estabHsh certain rock groups 

 in a. typical area will be followed by a description of the extension of the 

 roek^ over the remaining field. Before describing the rocks, however, I 

 shall discuss the facts relating to the general structure and the boundary of 



