32 NEW YORK STATE MUSEUM 



in length; these layers mostly dipping to south. (2) Layers of dark 

 sand mixed with pebbles and worn fragments of shale rock 3 to 10 

 feet thick. (3) Thinner layers of stratified yellow sands a few 

 inches to 3 or 4 feet thick. 



A gravel pit and slope showing a thickness of about 40 feet 

 occurs along the road that crosses the eroded area northwest of 

 Waterford near where the small stream crosses the road. This is 

 apparently an exposure of the same gravel mass described in the 

 preceding paragraph. Also on the northern part of Peobles island, 

 south of Waterford, sand and gravel are obtained from deposits 

 which apparently fill depressions of the rock surface. The materials 

 show a stratified arrangement and consist of water-worn fragments 

 of rock, ranging from the size of pebbles to cobbles, with irregularly 

 interstratified layers and lenses of coarse sand, mingled with worn 

 fragments of local rock. 



These bodies of gravel are interpreted as representing kames, 

 or morainic accumulations formed at the ice front in the retreat 

 of the ice lobe which occupied the general valley of the Hudson 

 after the melting of the ice from the uplands. As lacustrine condi- . 

 tions supervened these ice deposits were covered over with the 

 clay sediments but in the localities mentioned, as elsewhere on the 

 floor of the Hudson, they have been stripped of the clays and more 

 or less reduced by stream erosion. 



An interesting occurrence of gravels is that found on Green 

 island and on the east side of the river, south of Lansingburg. 

 Here the surface materials are limited to a thin layer of coarse 

 sand and fine gravel immediately overlying bedrock. The thick- 

 ness of this deposit, as observed, is nowhere in excess of 3 or 4 

 feet and in places it thins out to a few inches. The deposit lies 

 unconformably on the rock surface, filling and smoothing over 

 depressions in the rock. These sands and fine gravels are inter- 

 preted as outwash deposits from the morainic accumulations to the 

 north and referred to in the preceding paragraphs. 



The Willow Glen gravel bank. At Willow Glen the north 

 slope of the valley now followed by Anthony kill presents an 

 exposure of a thick mass of sand and gravel. The materials are 

 utilized for building purposes and a spur of the railroad extends 

 to the bank. The general composition and structural features are 

 similar to those of the sand and gravel bank at North Albany. In 

 general, the entire mass shows irregular stratification : layers of 

 coarse gravels intermixed with coarse sands are clearly marked off 



