696 GEOLOGY OF OLD HAMPSHIRE COUXTY, MASS. 



juuction is such as can have been formed only liy the fovcibh? kneading 

 tog-ether of the beds. A little farther south, on the border of the delta at 

 the house of Captain Briggs, the red sands come to the surface in a long 

 knoll. They are finely cross-stratified and dip south with an angle as high 

 as 35°. At the cutting these under sands are much jointed and faulted, as 

 if they had been subjected to pressure before the deposition of the upper 

 sands. I identify these lower sands with the pink sands of the Camp Meet- 

 ino- cutting (p. 680), and believe them to be a remnant of beds deposited after 

 the first recession of the glacier, while the Deerfield Valley was still sealed 

 up by the ice, which escaped the erosion of the second advance of the ice 

 and on its recession were covered by the sands of the Deei-field delta. 



It is not clear to me what could have caused the extensive disturbance 

 of the upper sands. This disturbance is to be seen in the upper side of the 

 road running parallel to the cutting, several hvmdred yards to the east. It 

 is at its maximum at the north end of the opening, where the sands have 

 been removed by the erosion of the river and extended an unknown dis- 

 tance to the north in the beds before their removal. 



On the north side of the Deerfield River basin, a mile west of Cheapside, 

 a complete section of the sands from the surface down to the till was quite 

 normal and undistm-bed, as also on its northwest l:)order and on the island 

 of the terrace sands which rises in the middle of the basin. Small detached 

 areas of disturbance in the delta sands are conimon from the head of the 

 latter south to the south line of Deerfield, plainly caused by stranded ice, 

 but here a force of much greater magnitude was cei'tainly concerned. 



I have described on page 630 the deep, long depression along the west 

 line of Greenfield in which Grreen River flows and which was occupied 

 by tlie west lobe of the ice that found place in the valley while the flood 

 sands brought in across Greenfield through the Bernardston strait were 

 building up the high terrace in Greenfield, and this lobe of ice, extended 

 south, would have come in contact with the delta of the Deerfield from the 

 right direction to have plowed up the sands as we now find them. The higli 

 terrace sands are, however, undisturbed right across its supposed track west 

 of Cheapside, and though these sands may have been swept in a little later, 

 their presence renders this explanation only remotely probable. Another 

 possible explanation is that the axis of the delta of which these beds form 

 a part lay to the north of this spot, and along this axis the greater thick- 

 ness of the beds caused, by their weight, a flowing of their fine sands. 



