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NEW YORK STATE MUSEUM 



of a glacier margin. The beaclilike evenness of the contour of 

 the base between the 260 and the 300 foot lines, the overlapping 

 epitlike projection extending from the base of the upper or Scho- 

 dack terrace southwestward on the north bank of the Moordener 

 kill to Schodack Depot, as well as the character of the drift along 

 this slope at the level named, are strongly suggestive of a water 

 level between 260 and 280 feet. Between these two levels the bed 

 rock is exposed in low ledges as if from the effects of wave strip- 

 ping. The annexed diagrammatic section east and west in the 

 latitude of Vierda kill illustrates the relation of the Schodack 

 terrace to the lower terrace confronting the Hudson gorge. 



[C£-_SHE£T. 



SCHODACK 



~ CENTRE. 



Fig. 14 Cross-section of delta terrace, near Vierda kill. K, kettle hole 



South Bethlehem terrace. On the opposite or western side of 

 the Hudson valley there is a small dissected terrace at the mouth 

 of Oniskethau creek with its base resting on the old valley floor 

 of the Hudson just west of the village of South Bethlehem. This 

 terrace likewise rises abruptly from the low broad clay plain 

 adjacent to the Hudson trench to the hight of 260 and 280 feet 

 above the sea. The large remnant of the deposit on the south 

 bank of the Oniskethau is totally unlike an ordinary delta built 

 in an open water body. The outer margin overlooking the clay 

 plain has a raised rim with a gentle slope for some rods back 

 to the westward or upstream and the surface of the terrace is 

 strewn with angular blocks many of which have now been gath- 

 ered into fences. The long bar rising to the hight of 260 feet on 

 the north bank of the stream is gravelly on its western slope but 

 coated with till on the slope toward the valley in the manner of 

 an ice contact. In fact, every feature of the outer slope of this 

 terrace indicates that the deposit was made in a depression be- 

 tween the hills and the ice margin when the glacier filled the 



