292 GEOLOGY OF THE IJ^AERAGANSETT BASIK 



at the top including fragments of coaly shale, followed by a 4-foot layer of 

 conglomerate, also including fragments of coaly shale at the top. Above 

 the conglomerate are 2 feet of coaly shale, 12 feet of conglomerate, 6 feet 

 of coaly sandstone, 15 feet of grayish-black sandstone, 5 feet of grayish 

 sandstone, 2 feet of black coaly shale, 14 feet of dark-gray sandstone, two 

 layers of conglomerate 15 and 7 feet thick, 13 feet of sandstone, and, at the 

 top of the section, three layers of conglomerate, 33, 23, and 27 feet thick. 

 A generalized statement of the chief characteristics of this section would 

 be 82 feet of coarse conglomerate at the base, followed by 99 feet of sand- 

 stone, 41 feet of coarse conglomerate, 42 feet of sandstone, and 118 feet of 

 conglomerate. The thickness of the great interbedded sandstone layers 

 should be especially emphasized when the attempt is made to determine 

 the relative horizon of isolated small sandstone and coarse conglomerate 



outcrops. 



Along the line of outcrop described above, the dip varies, southward, 

 from 60^ E. to 45^ and 40° E., becoming again 60° E. toward the southern 

 end of the section described. Southward along the shore, at a promontory 

 a mile south of Black Point, the dip increases to 80° E. The steep east- 

 ward dip continues southward, becoming 80° W. at Taggarts Feriy Cove, 

 but returning to 75° E. again on the south side of the cove. 



The very coarse conglomerate borders the eastern shore of Aquidneck 

 Island as far southward as the north end of Smiths Beach, except in the 

 cove two-fifths of a mile north of Woods Castle, known as Taggarts Ferry, 

 where rocks occur varying between coaly sandstone and coaly shale. 



On the shore west of the southern end of the cove, and along the 

 creek south of these exposures, dark carbonaceous shale and sandstone are 

 exposed for 30 or 40 feet. The shale series is believed to merge gradually 

 upward into this peculiar coaly, carbonaceous shale and sandstone. East- 

 ward along the shore overlying these land exposures is more sandy rock of 

 the same character. Overlying this is found a coarser sandstone, overlain 

 in turn by carbonaceous shaly rock, the dip varying from vertical to 85° 

 W. Then comes, eastward, a coarser sandstone, with small pebbles, dipping 

 80° W. Toward the north, along the shore, a sudden twist causes the con- 

 tact between this rock and the overlying carbonaceous shale to dip due 

 east Faxther east, coarser sandstone, with fine conglomerate overlying it, 



