UPPER SERIES OP KEENE VALLEY GROUP 653 



KEENE VALLEY GROUP 



Upper series — Western section. — As the ice-sheet began to wane, the 

 highest peaks of the Aclirondacks were the first to become uncovered, and 

 played the role of islands in a sea of ice. 11 Slowly these islands became 

 larger, surrounded, by a growing accumulation of water impounded by 

 the ice. The waters found escape over the ice to the south and eventually 

 passed to Susquehanna drainage. This process of melting was continued 

 until entire mountain ranges were exposed. 



South Meadows Lake (altitude, 2,000 to 2,040 feet).— The falling- 

 waters, still hemmed in by the ice, came finally to a pause sufficiently long 

 enough to leave a group of terraces and sand plains at the present altitude 

 of 2,000 to 2,040 feet, chiefly in the South Meadows country. This great 

 sandy deposit, already referred to, is open to two interpretations : first, 

 that it is an outwash plain spread out by the waters from the retreating 

 ice ; and, second, that it is a glacial lake bottom. The writer is inclined 

 to favor the latter hypothesis, and so has proposed the term "The South 

 Meadows Lake." 



Although the terraces of this lake are chiefly found on the Mount Marcy 

 sheet, the adjacent corners of the Santanoni and Saranac quadrangles 

 exhibit remnants. 



The fill in the South Meadows is enormous. It must have taken a 

 long time for entering streams to wash such a large amount of material 

 into the standing waters of the lake. Undoubtedly the original surface 

 till furnished some of the material. The terraces blend with the boulder 

 drift on the mountain slopes and attain an altitude of something over 

 2,100 feet at the valley walls. A number of kettle-holes dimple its sur- 

 face, several of them now occupied by ponds, Round Lake being an 

 example. 



The position of the northern ice-front at this stage is not definitely 

 known, but no terraces have been found north of a line drawn east and 

 west across the Lake Placid quadrangle through the southern end of the 

 lake. On the Saranac and the Santanoni sheets the ice is for the present 

 assumed to have lain on a line connecting the summit of Ampersand 

 Mountain and the shore of Lake Placid at the point where Whiteface Inn 

 is now located. This position is suggested on the basis of a probable 

 outlet for the lake to the west as follows. It begins at the swamp just 

 south of Alford Mountain, in the Santanoni quadrangle, on the Essex- 

 Franklin County boundary line, it passes westward through the narrow 

 pass (altitude, 1,960 feet) directly south of Van Dorrien Mountain to 



11 H. L. Fairchild : N. Y. State Mus. Bull.. No. 160, pi. 11. 



