320 GEOLOGY OF THE NAREAGANSETT BASIN. 



northward from this road, along the Newport road, the blue-black shale 

 fragments, apparently almost in situ, show frequent fern-leaf impressions. 

 Farther northward, in the roadside, greenish shale occurs. These green 

 shales are seen again east of the road on the northwestern side and along 

 the summit of the hill, and are overlain on the eastern side of the hill by 

 fine-grained grayish-green sandstone striking about N.-S. and dipping 30° 

 to 40° E. This sandstone is exposed again northward along the strike on 

 the west side of the road. This exposure serves to confirm the evidence 

 of the general eastward dip of the rocks along the western side of the 

 island, a feature so much better shown to the northward. The dark green- 

 ish-blue shales are also well exposed where Lawtons Valley crosses the 

 east-west road leading toward the Grlen. 



GREENISH-BLUE SHALES OF SLATE HILL AND SOUTHWARD. 



Along the East Newport road, east of the highest part of Slate Hill, 

 bluish shale tinged with green is exposed west of the road. A quarter of 

 a mile southward the shale, here colored dark blue, at one point verging 

 to black, occurs interstratified with sandstone. The strike is N. 15° E., dip 

 apparently low E., about 10°. Half a mile southwest along the road, 

 where it begins to descend the hill more rapidly, the greenish-blue shale is 

 exposed, and three-eighths of a mile farther on it is seen for the last time 

 on the west side of the road. The isolated conglomerate exposure three- 

 quarters of a mile farther southwest has already been mentioned. 



SHALE SERIES NORTH OF LAWTONS VALLEY. 



SHORE EXPOSURES NORTH OF COGGESHALL POINT. 



Coaly shale is exposed along the shore three-quarters of a mile north 

 of Portsmouth Grove Station and continues northward. Near Corys Lane 

 fine-grained sandstone overlies the shale and contains plant impressions. 

 North of Corys Lane the shore offers material for a detailed partial section 

 as follows, in descending order, going northward: 



Section north of Corys Lane. 



Feet. 



Fine sandstone 15 



Black coaly shale, containing Sphenopliyllum equisetiformis, Annularia longifolia, 



and large fern- frond impressions 9 



Sandstones, in places somewhat coarse 7 



