174 GEOLOGY OF THE NARRAGANSETT BASIN. 



allel, but the dip joints are much less regular planes. One-fourth of a 

 mile west of this locality there is a long ridge of alternating grits and 

 conglomerates, probably the outcrop of the heavy conglomerate which 

 comes in more distinctly farther north. The beds are penetrated by nests 

 and veins of white quartz. In the shales underlying one of the sandstone 

 ridges impressions of calamites and asterophyllites were found in the course 

 of the present survey by Mr. W. E. Parsons. 



seekonk conglomerate. — North of this area, about a mile along the strike, 

 the geological structure and topographical features are repeated. The See- 

 konk conglomerate bed here becomes more pronounced and can be traced 

 along the east bank of a small brook for the distance of a mile. It is from 

 50 to 60 feet thick, very massive, and contains quartzite pebbles from 3 to 

 6 inches in diameter. Where weathered the pebbles fall out of the matrix 

 readily and show little or no dynamic metamorphism. The resemblance 

 of this bed to the conglomerates of the Dighton group is very striking, and 

 the bed may be tentatively considered the equivalent of the coarse con- 

 glomerate which occurs at the base of this group. It is so represented 

 on the map. 



The strata in the northern part of Seekonk turn northeast, and then 

 due east and pass into Rehoboth, and so continue on to the tract mapped 

 on the Taunton quadrangle. Very good exposures may be seen along the 

 road about half a mile north of the head of Wolf Plain Brook. A coarse 

 conglomerate north of the road in the edge of the woods is probably the 

 continuation of the Seekonk conglomerate. It is overlain by sandstones 

 and pebble beds which dip from 5° to 10° S. 



The strata just described in Seekonk and in the northern part of 

 Rehoboth, as shown on the Providence quadrangle, form the western part 

 of a broad, square-ended syncline. About 3 miles south of the point where 

 the Seekonk beds turn from northerly to easterly strikes they again strike 

 eastward to make the southern side of the Great Meadow Hill syncline. 

 Some minor folding appears between this point and Great Rock. 



The southern part of Seekonk and Rehoboth is heavily drift covered, 

 and outcrops are from 2 to 3 miles apart and not in sufficient number to 

 give much value to the interpretation of the structure in this part of the 

 field. About 2 miles south-southeast from the Davis Carpenter place a 

 coarse conglomerate striking E.-W and dipping 80° N. comes in, over- 



