ROCHESTER AND ONTARIO BEACH QUADRANGLES 31 



but in the Rochester section they have never been found. Whether 

 the edges of the salt beds extend as far north as the Rochester 

 region is not known. The beds occur a few miles south of this 

 region where several shafts and wells have penetrated the rock salt. 

 It must be remembered, however, that at the time of the deposition 

 of the salt the Salina sea was at its minimum extent and the salt 

 beds would be restricted to a much smaller area than the Vernon 

 shales which precede them, and hence beds of rock salt may never 

 have extended over any of the Rochester area. Again the salt 

 beds if they ever extended far enough north to outcrop, must have 

 been almost completely dissolved by the action of surface and 

 percolating waters. The presence of salt^springs about the middle 

 of the outcrop of the Salina series, extending from Syracuse 

 westward is very suggestive of the former presence of rock salt 

 within this area. 



Camillus shale. These beds take their name from Camillus in 

 Onondaga county. They contain all the workable beds of gypsum 

 found within the State. They extend as far east as Albany county 

 and west beyond the limits of the State. Gypsum is mined and 

 quarried from this formation at many points from Buffalo to east of 

 Syracuse. West, just beyond the limits of the map, the gypsum is 

 mined at Wheatland. The most extensive beds of gypsum are at 

 the top of the formation and, at Union Springs, are 50 feet thick 

 including a few thin bands of shaly material. 



The thickness of the Camillus shale varies considerably, but the 

 average thickness is about 300 feet. The formation includes a 

 number of thick layers of magnesian limestone. The shales are 

 quite soft and in color vary considerably. They include layers of 

 red and mottled shales, which alternate with gray and olive green 

 shales containing thin seams of gypsum. As before stated, the 

 only fossils noted from the Camillus shale are L e p e r d i t i a 

 scalar is and a form of Meristella. These are found in the 

 magnesian limestones of this formation. 



Bei'tie waterlime. This waterlime terminates the Salina series and 

 is the highest formation represented on the map. The term is from 

 Bertie, a town in Ontario, 12 miles west of Buffalo. The name was 

 long ago applied by Chapman to the Eurypterus-bearing water- 

 limes of that place. The formation is known to extend from 

 Canada as far east as Schoharie county and throughout this extent 



