rl26 NEW YORK STATE MUSEUM 



three lower channels of the group on the north slope of West 

 Stockbridge hill, all of which are in Salina shale. Being coni^ 

 posed of shale debris, the delta has weathered into erosion 

 forms, and from the north looks like a moraine, but seen from 

 the proper hight, specially from the south, its plateau character 

 is conspicuous (pi. 37). 



At High Bridge, south of Fayetteyille, is a broad delta rem- 

 nant of coarse gravel, with map altitude of 600 feet. This is ai 

 portion of the deposit left by the river that excavated the White 



lake gorge. 



Cataract lakes 



Origin. The peculiar lakes in the region southeast of Syracuse 

 have been a subject of comment and speculation for over half a 

 century. These lakes are notable for their location, being in 

 amphitheaters with very steep or even vertical walls of lime- 

 stone; for their considerable depth as compared with their area; 

 and for the clearness and color of the water, which hais caused 

 multiplication of the name. Green lake. Many more or less 

 reasonable and unreasonable explanations of the origin of these 

 lakes have been given: that the basins were of volcanic origin or 

 craters; that they were produced by sinking of the strata, due 

 perhaps to solution of the limestone or of the underlying salt 

 beds; and that they were the result of surface solution of the 

 rocks. 



The true explanation of the genesis of these lakes is now per- 

 fectly clear. They occupy cataract or plunge basins, similar to 

 that which would exist at the foot of Niagara falls if the Niagara 

 river were to be withdrawn. Indeed, the cataracts which exca- 

 vated the Syracuse basins were actually the predecessors of 

 Niagara, as they were produced by the falling of the waters of 

 the Erie-Huron basin from the Erian level down to the Ontariaa 

 (at that time the Iroquois) level. The lakes all lie in the heads^ 

 of channels cut by the sub-Warren waters. 



No lakes have been found in the plunge basins of the higher 

 channels, though the dry basins exist, probably because they have 

 limestone foundations. The basins holding lakes' seem to be either 



