r22 



NEW TOBK STATE MUSEUM 



Herkimer and TItica lakes 

 This name is applied to such standing waters as the ice front 

 held in the Mohawk valley above Little Falls [see pi. 2, 13]. 

 They were never large and their extent is uncertain. The possi- 

 bility of lake waters in the valley has been recognized by former 

 writers, 1 but the relationships and sequences have not been 

 discussed. 



A rock barrier, which will be described later in this writing, 

 existed at Little Falls when the glacier melted away from the 

 region, and probably some ice drift was left over it. But no 

 such lake ever existed in the valley above Little Falls as would 

 be produced there today if the rock barrier could be restored, 

 for the reason that the present graded valley, under the 500 

 foot contour, is partly the product of river action, chiefly by the 

 Iromohawk (contraction for Iroquois-Mohawk) with some effect 

 of the modern stream. In other words the capacity of the present 

 valley is greater by whatever amount of drift the rivers have 

 removed. 



The 7 miles of valley from Little Falls to Herkimer must have 

 been partially occupied by glacial drift, and such lake as rested 

 here when the ice was first removed, the Herkimer lake, might 

 have been at least partly filled by the detritus of West Canada 

 creek. Brigham suggested that the water-laid drift on the 

 south side of the valley at Herkimer might be the front of the 

 eroded delta. Even today the river is crowded to the south 

 side of the valley. At Frankfort and Ilion the deposits were 

 possibly sufficient to block the valley, for to the detritus of the 

 side streams was here added that of the floods of glacial rivers 

 which terraced the hills southeast of Utica [see p. r27]. 



The initial lake waters at Little Falls were probably not less 

 than 600 feet altitude, as that is the hight of the water-swept 

 rock on the north side of the barrier. The same sloping rocks 

 on the south side [see p. r31J are about 500 feet, which may be 

 * 



'Chamberlin, T. C. Terminal Moraine, etc. U. S. Geol. Sur. 3d An.^Rept. 

 p. 361-62. 



Taylor, F. B. Letter in Am. Geol. May 1892. 9:344. 



Brigham, A. P. Topography and Glacial Deposits of the Mohawk Valley. 

 Geol. Soc. Am. Buf. 1898. 9:188-210. 



