316 GEOLOGY OF THE ^AREAGANSETT BASI^^. 



beach there occnrs an additional mass of the greenish igneous rock, trav- 

 ersed in all directions by whitish streaks. This is probably a continuation 

 of the greenish rock from the eastern shore, near Sheep Point. 



GRANITE AREA ON EASTERN NEWPORT NECK. 



At the western end of the beach, south of Almys Pond, is found a 

 reddish granite, to a certain extent resembKng the gronndmass of the por- 

 phyritic granite already described, but lacking phenocrystb. Toward Lily 

 Pond the granite has changed from bright red to a much darker red, due to 

 the presence of an abundance of some darker mineral. These granites are 

 frequently cut by the pinkish fine-grained aplite, whose character as a dike 

 rock is unquestionable in all of the more western exposures. This second 

 granite area includes all of the rock between Almy^s and Lily ponds, the 

 hill immediately west of Lily Pond, and thence northward as far as the 

 southern margin of the harbor at Newport, excepting perhaps a narrow 

 border along the shore, which seems to be made up of greenish shales similar 

 to those found elsewhere about the harbor. It occurs also as a medium- 

 coarse granite north of Ahnys Pond, in the western part of Morton Park. 



GREENISH AND PURPLISH ARGILUTIC ROCK OF MIDDLE NEWPORT NECK. 



West of the granite area, as far as Brentons Cove, the western side of 

 Rocky Farm, and Prices Neck, occurs a fine-grained rock, varying in color 

 from green to dark purple, in places epidotic, which has usually been called 

 an argillite. It contains traces of banding very similar to stratification, but 

 which might be iiiterpreted as flow structure. In the northwestern part of 

 this area Prof T. Nelson Dale found a fragment of undoubted quartz- 

 porphyry embedded apparently in a cement composed of clastic material 

 This would indicate that at least a part of the area was of sedimentary 

 origin. This rock is closely related to the Dumpling Rock and the greenish 

 rock southwest of Sheep Point. 



PRE-CARBONIFEROUS GREEN AND PURPLE SHALES OF WESTERN NEWPORT 



NECK. 



The western part of Newport Neck, including all the area west of a 

 Kne drawn through the marshes from the western side of Prices Neck to 

 the southern end of Brentons Cove, is occupied by a series of shales. 



