294 GEOLOGY OF THE NAEEAGANSETT BASIN. 



CO VRSE CONGLOMERATES AJSTD UJSTDERLYIIJ^G BOCKS OK THE NECK 



AT EASTONS POUnTT. 



On the eastern side of the neck, at the west end of Sachuest Beach, 

 the very coarse conglomerate series is well exposed along the shore for a 

 length of almost half a mile, terminating southward in a long narrow 

 promontory projecting into the sea. The strike of this conglomerate is 

 about N. 20^ E., dip 60° E.^ southward becoming only 45 '^ E. West- 

 wardy beneath the conglomerate is greenish sandstone, often shaly. Inter- 

 bedded with this is conglomerate, but not equaling the sandstone in 

 quantity, and the pebbles are also much smaller than those in the very 

 coarse conglomerate. The dip is still 45° E. South westward along the 

 shore, still lower rocks are exposed — ^greenish shaly sandstone and shale, 

 with conglomerate of rather small pebbles. The dip is 45° E , and the 

 strike is still N. 20° E. Thence to Eastons Point there is a series of 

 underlying greenish shaly sandstone and fissile shales, having an eastward 

 dip. So far the exposures beneath the coarse conglom^erate are so little 

 divergent from the strike of the shore line that the section as far as the 

 point does not represent any great thickness. Going northwestward from 

 the point, we meet still lower rocks. At first greenish shaly rock continues 

 the descending section, containing a little conglomerate a short distance 

 west of the point. At one point west of the southern end of the neck ripple 

 marks are seen in the shales. Nine hundred feet northwest from the point 

 intercalated sandstones indicate a local increase of dip to 70° E., and then 

 toward the axis the dip is lower eastward The axis of the anticlinal fold 

 is about a third of a mile northwest of Eastons Point. The dip on both 

 sides is low. The pitch of the fold is about 10° S. 



West of the anticline the dip is at first low W, 20°. This continues 

 for some time until, about half a mile from the point, the dip increases to 

 45° W., the strike being still N. 13° E. Here are intercalated gray sandstone 

 and conglomerate composed of small pebbles corresponding to the con- 

 glomerate just west of Eastons Point. Farther northwest the conglomerate 

 layers become rather frequent, the dip being 45° W.; and this continues for 

 some distance along the shore The pebbles are only of medium size. 

 Locally the dip becomes steeper west, at one point 80° W., but it soon returns 

 to very low west, and then 45° W. again; near this point the very coarse 

 conglomerate makes its appearance once more, about three-fifths of a mile 



