24 



NEW YORK STATE MUSEUM 



The north slope of the high ground west of Marcellus station, 

 the latter situated at the mouth of the Marcellus or Ninemile creek 

 valley, is also extensively benched and channeled by water flow 

 that was synchronous with the Split Rock rivers. Locally the dis- 

 trict is known as Lime Ledge. 



All the stretch of water-swept limestone from Lime Ledge east to 

 at least the Syracuse city line, a distance of 9 miles, has been 

 affected by postglacial sinkage of the strata, similar to that in the 

 Caledonia-Leroy district, described on pages 12-14. The disloca- 

 tion of the naked limestones is conspicuous in the channels at Lime 

 Ledge, and it may be clearly recognized from the electric railway 

 throughout the Split Rock district. Immediately east of the Split 

 Rock gorge, by the first road crossing, the Salina shales are so 

 broken that it is not easy to discriminate the forms, whether pro- 

 duced by sinkage and dislocation, stream work, weathering of the 

 soft rocks, or moraine remnants. West of the city in the low chan- 

 nel many mounds and subdued forms, at 420 to 460 feet, which 

 resemble moraine masses are found to be remnants of the Salina 

 (Camillus) shales left by the ancient stream erosion and modified 

 by weathering. In the low channels both east and west of Syracuse 

 the eroded and weathered Salina shales are easily mistaken for 

 moraine. This is also true of some upland surfaces, specially noted 

 in the Canastota-Oneida region, where the drift is scanty and the 

 land surface has not been rubbed or drumlinized by the ground- 

 contact ice [see title 39, p. 431]. 



There is no question that all the channels of the Split Rock series, 

 as well as all the lower channels on the north, were carved by east- 

 ward water flow. The highest unmistakable cutting is the one 

 already noted as lying south of the Howlet Hill-Onondaga Hill 

 highway. On the north slope of Howlet Hill and on the brow of 

 the hill to the west the surfaces are comparatively smooth, as if 

 water-swept, across surfaces which the map contours make 920 to 

 940 feet. Theoretically it seems possible that such smoothing 

 might haye been done by westward flow into Lake Hall, toward the 

 Batavia escape. There should have been westward flow on this 

 meridian at all levels from the Navarino channel, 1060 feet, down 

 to the level of the Batavia channels, near 900 feet. The successors 

 to the Navarino channels arc three or four small cuts across the 

 nose of the hill sm^heast of Marcellus, at about 1020 down to 960 

 feet. The f this rtieridian, terminating in Howlet -Hill, 



would seem ' ^en the critical and dividing line where the 



