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NEW YORK STATE MUSEUM 



Chapter 9 



LARGER GLACIAL LAKES OF THE CHAM PLAIN AND 

 HUDSON VALLEYS (continued) 



LAKE VERMONT OR GLACIAL LAKE CHAMPLAIN 



From the failure of the higher shore lines of the Lake Cham- 

 plain district to pass around the northern spur of the Adirondack^ 

 at Covey hill and thus westward along the northern flank of the 

 mountains it seems as before stated necessary to postulate an ice 

 dam across the mouth of the Champlain valley acting as a barrier 

 to retain the waters in it up to these higher levels. The waters 

 thus confined in the Champlain valley already recognized by Bald- 

 win, Upham and others, have been referred to as glacial Lake 

 Champlain. As this body of water was of far greater extent 

 than Lake Champlain and came into existence independently of 

 this smaller lake and moreover was separated in time from Lake 

 Champlain by a marine episode in the valley, it seems best to 

 employ a distinctive name. As the glacial lake covered practi- 

 cally much of the state of Vermont west of the Green mountains 

 and probably penetrated through that range at its highest stages 

 to the basins on the east of the mountains, " Lake Vermont " is 

 used here instead of the descriptive phrase heretofore employed. 



This body of water was apparently at first as noted by Upham 

 confluent on the south with what is in this paper denominated 

 Lake Albany. Just how far north in the Champlain valley the 

 ice had retreated at this early stage depends on the interpreta- 

 tion of the higher gravel ridges and beachMke deposits in the 

 northern half of the Champlain valley. On the extent to which 

 the ice had retreated depends in turn the extent at any time of 

 the lake toward the north. The outlet of these ice-dammed waters 

 at this early stage of confluence across the present divide of the 

 Hudson and Champlain basins is a matter which concerns the 

 interpretation of Lake Albany on the south and is considered in 

 that connection. Lake Vermont may be said properly to have 

 come into existence when in consequence of a local lowering of 

 the waters south of Fort Edward a discharge began across a bar- 

 rier into the Hudson valley on the south. 



