28 , NEW YORK STATE MUSEUM 



cases very heavily topped with a shale and limestone cap which 

 must be stripped in quarrying, since it appears too badly broken up 

 to allow tunneling miethods. 



Owing to their somewhat irregular character and to their rela- 

 tively low percentage of g}^psum, the more inaccessible deposits in 

 this region have little present value, while even the more favoirably 

 situated and larger lenses are of limited utility. 



Onondaga county 



The Salinia shales outcrop in Onondaga county in an east-west 

 belt varying in width from lo to 12 miles. The lower beds, known 

 as the Vernon red shales, outcrop in the northern portion in Ly- 

 sander. Van Buren, Clay, Salina, Cicero and Manlius townships. 

 They are described by Luther^' as including many layers of green 

 shales and mottled red and green shales. " The red color is, how- 

 ever, very pronounced, a strong brick-red; the green is a light but 

 generally distinct pea-green. Some of the upper layers near the 

 contact line are olive. Red is the predominating color in the lower 

 beds, and green toward the top. The shale is very soft and clayey, 

 crumbling into dust on exposure, if diy, or turning to clay, if wet. 

 , Some of the green and olive layers are fissile to a slight degree." 



Overlying these shales and outcropping to the south are a series 

 of peculiar, cellular, broken limestones containing hopper-shaped 

 cavities, seams and irregular cavities. These are accomipanied by 

 dark gypsiferous or olive colored shales. This is supposed to be 

 the horizon of the salt beds of the State and at the surface, along 

 the outcrop, numerous salt springs were once abundant. Above this 

 horizon and to the south lie the gypsum or Camillus shales. They 

 occupy a belt 2^^ to 3 miles in width and are bounded on the south 

 by the ridge which is a prolongation of the Helderberg escarpment. 

 They also extend in long tongues to the south through the escarp- 

 ment in the valleys of Limestone, Butternut, Onondaga, Marcellus 

 and Skaneateles creeks. The gypsum series consists oi gray, drab 

 or mottled shales with interstratified layers of fine-grained platten 

 dolomite, and contains many thick beds oi grayish to black gypsum 

 and gypsiferous shale. Between the two chief gypsum masses, 

 according to Luther,- there lies a 40 to 50 foot course of dolomite 

 or clayey limestone, containing numerous cells and cavities and 

 formerly known as " vermicular limerock." The gypsum beds 



' N. Y. State Geol. Rep't 15.1898. 1 12 50. 

 ^ Ibid. p. 264. 



