714 PROCEEDINGS OP THE OTTAWA MEETING 



features have been described by Professor Woodworth for the Mooers quad- 

 rangle.* 



Doctor Gilbert had also noted shore phenomena, cliffs and bars, in the dis- 

 trict east of lake Ontario which he regarded as the work of the sealevel waters. 

 These were subsequently seen by the writer, and in the summer of 1905 these 

 supposed marine features were traced with some care from a point on the 

 Ontario shore a mile northeast of the hamlet Texas, and about 14 miles north- 

 east of Oswego, northward to near Henderson village, through a stretch of 

 about 21 miles. 



Throughout this district the cliffs, spits, and bars are well developed, as 

 shown in figures 1 and 2. The approximate altitudes of the features are in- 

 dicated by the map contours. The spit near Texas is about 16 feet over the 

 lake, or 262 feet above tide. The highest bars in the region of Henderson are 

 from 310 feet to 320 feet altitude. The lower may not represent the full 

 height of the water surface, as they were built out some distance from the 

 shoreline and are not very coarse material. The spit at Texas is very coarse 

 material and probably is a storm beach; but, taking the features as they lie, 

 the rise of 53 ± feet in 21 miles of right line distance shows a deformation of 

 at least 2.5 feet per mile. 



The bars occur at various levels, beneath the highest one, down to the present 

 lake. This is to be expected of the work of marine waters here, because the 

 change of level in relation to the land surface was due to continental uplift, 

 which was a process sufficiently slow to allow effective wave work at all infe- 

 rior altitudes. It might not unreasonably be expected that shore phenomena 

 would be found at levels intermediate between the Iroquois beach and these 

 supposed marine beaches, which should represent the long pauses in the lower- 

 ing of the sub-Iroquois waters while the overflow was cutting the rock chan- 

 nels near the north border of the State ; but such features do not occur, though 

 wave-swept areas of limestone are found. f In the beaches under discussion we 

 apparently have the effects of wave-work at planes of water level much more 

 enduring than was possessed by the sub-Iroquois waters with shifting outlets. 



The positive proof that these beaches were made at sealevel would be the 

 finding within them of marine fossils. Casual search has not yet discovered 

 any fossils of either fresh or salt water. However, the absence of fossils would 

 not be conclusive; and even the presence of fresh-water shells might not be 

 positive proof against sealevel attitude, as it might be held that the long and 

 narrow Saint Lawrence strait and the outflow of copious glacial waters might 

 prohibit the inflow of salt water. It seems likely, however, that the strait was 

 sufficiently deep (more than 150 over the present river surface) and sufficiently 

 wide (many miles after the ice-front backed away) to allow the waters to be- 

 come at least brackish. 



Whether the waters which produced these beaches were open to the sea or 

 not, they deserve a distinctive name. They are neither Iroquois nor Ontario. 



* J. B. Woodworth : Pleistocene geology of the Mooers quadrangle. Bulletin 83 

 (geology 7), New York State Museum, 1905. 



f In the falling of the glacial waters in central New York from the Warren to the 

 Iroquois level, or from 880 to 440 feet, only one pause has heen found of sufficient 

 endurance to produce conspicuous shoreline features, that of lake Dana at 700 feet 

 although capacious rock canyons were cut in the district of Syracuse. 



