34 NEW YORK STATE MUSEUM 



Report of the State Geologist for 1902 (see title 17). Similar to 

 these waters held along the south margin of the lobe were other 

 local waters on the north side. 



The high ground between the Ontario basin and the Black vaJJey 

 must have emerged from the ice sheet as an island in the broacr 

 water (plate 13). When this land mass became connected with 

 the exposed land on the southeast (plate 14), or even earlier, the 

 land drainage and the glacial outwash passed around the periphery 

 of the open area until it reached the Mohawk escape. The greater 

 portion of the high area is today drained westward by the numerous 

 branches of North Sandy and South Sandy creeks, Salmon river 

 and lesser streams, and southward by the west and east branches 

 of Fish creek and the Mohawk river. All this heavy drainage was 

 blocked by the ice during the time shown in plates 14-16. Each 

 valley must have held its lake, and these poured from one into the 

 other across the intervalley ridges until the augmented water 

 reached the Mohawk valley. An example of such transverse chan- 

 nels is indicated in plate 4, in the vicinity of Lorraine east of Adams. 

 The fragmentary channels here noted .belong to a late stage of the 

 ice recession in the district, but similar cross-ridge channels must. of 

 necessity occur higher on the slope and of earlier time. Plate 2 

 shows one strong channel of the earlier drainage lying between Fish 

 creek and the upper Mohawk. No attempt is made to map the 

 minor channels, to do which will require close examination of large 

 territory. 



Lansing kill lake. These few channels in plate 2, between Fish 

 creek and the Mohawk, point us to the story of a distinct lake in 

 the upper Mohawk district. When the ice margin had the position 

 that is shown in plate 15 it formed an east-west dam lying on 

 Quaker and South hills. All the west and south drainage of the 

 highland east of Ontario basin flowed along the ice edge, producing 

 larger ponding in the two valleys of Fish creeks, and outflowing at 

 Point Rock into the Mohawk and then into the Lansing kill lake. 

 This was subsequent to the opening of the Remsen channel, but 

 while the St Lawrence glacier was pushing a lobe up (south) the 

 Black valley. It will be remembered that earlier the Lansing kill 

 waters had been a branch of the Forestport lake, the connecting 

 strait being the head of the Lansing kill valley, north of Potato hill. 

 The time here recorded is that of the Port Leyden stage in the 

 Black valley and the late Schoharie and early Amsterdam stage in 

 the Mohawk basin. A profusion of delta terraces are found in the 

 upper Mohawk-Lansing kill basin which fall into three categories ; 



