KINGSTOWN SERIES OF NORTHERN CONANICUT. 339 



numbers, the total thickness of the Kingstown series in the southwestern 

 part of the Narragansett Bay area. It will be remembered that in the 

 northwestern part of this area, in Warwick and Cranston, the estimated 

 thickness was 11,200 feet (see p. 336). 



western shore of conamcut. — The rocks along the western shore of Conanicut 

 also bear considerable resemblance to the Kingstown series as exposed on 

 the mainland, owing' to the presence of abundant sandstones, but they are 

 still more similar to the strata exposed on Dutch Island, of which they are 

 probably the continuation. Along the shore opposite Slocum and Great 

 ledges there is considerable coaly shale, some of which, according to T. N. 

 Dale, 1 contains fern impressions. There is also an abundance of sandstone, 

 interbedded with which are subsidiary conglomerate layers with very much 

 elongated pebbles, bearing considerable resemblance lithologically to the 

 conglomerate of Dutch Island and the layer on the western margin of 

 Beaver Head. The strikes along these ledges practically follow the shore. 

 From Sand Point northward similar coaly shales and sandstones with 

 subsidiary conglomerate layers are exposed. The strike is nearly N. 3° E. 

 Along the entire western shore the dips are eastward, usually, however, 

 quite low. 



Eastern shore of conanicut. — While the exposures along thewesterii shore of 

 northern Conanicut can be safely correlated with the strata on Dutch Island 

 and western Beaver Head, the position and geological structure of the strata 

 forming the middle and eastern parts of Conanicut remain, to say the least, 

 problematical. East of North Point occur coaly shales, apparently showing 

 lateral squeezing from east to west. Along the eastern shore are found 

 coaly shales, at one point with fern impressions; also gray sandstones. The 

 strikes average N. 10° E., and the dip is usually very steep, nearly vertical, 

 but shows in places sudden variations which can most readily be reconciled 

 with crumpling. The cleavage often obscures the bedding. The absence 

 of conglomerate layers along the eastern shore is a conspicuous feature in 

 contrast with the more western line of exposures, including western 

 Conanicut, Dutch Island, and Beaver Head. The exposures along the east- 

 ern shore of northern Conanicut may therefore belong to another horizon, 

 possibly a higher one corresponding to the strata overlying the conglom- 

 erates on the western margin of both Beaver Head and Prudence Island. 



1 On metarnorphism in the Rhode Island coal hasin : Proc. Newport Nat. Hist. Soc, Doc. 3, 1885, 

 pp. 85-66. 



