32 



NEW YORK STATE MUSEUM 



Data for its location on this map are derived principally from 

 field work on the quadrangles at the south and west of this one, 

 the few exposures here not being sufficient for its positive identifi- 

 cation. 



Its position is approximately indicated on the map and its 

 assigned thickness is 75 feet. 



West Hill (Gardeau) flags and shale 



Except that the proportion of sandstones in the shales is some- 

 what greater and more uniformly distributed there is very little 

 difference between the stratification of this formation and the West 

 Hill beds below. They are, however, less fossiliferous. A few 

 representatives of the Ithaca fauna are found in all parts as are 

 also a small number of species common in the Naples fauna. 



Soft gray shales resembling the Cashaqua shale, exposed on 

 Butcher hill, in the upper part of this formation, contain obscure 

 goniatites, orthoceratites and Cladochonus, but no brachiopods. 



f 

 High Point sandstone 



This formation is important stratigraphically and economically in 

 the Genesee river section. There it contains only fossils of the 

 Portage fauna but is stratigraphically continuous with the High 

 Point sandstones of the Naples section where it contains mainly 

 brachiopods common in the Chemung fauna. It becomes shaly in 

 some parts toward the , east but can be traced at least as far as 

 the region south of these qua.drangles. There are here but small 

 isolated exposures of its horizon in small ravines on the higher 

 slopes of Butcher hill. 



Prattsburg sandstone-Wiscoy shale 

 Chernung sandstone 



The position of these formations at the crest of the high ridge 

 between the Seneca lake and Cayuga lake valleys where there are 

 no favorable exposures is indicated from data obtained on the 

 Watkins quadrangle. For description of these higher beds and 

 lists of fossils contained in them) see Museum bulletins 63, 81 and 



lOI. 



DIP 



The average dip of the rock strata on these quadrangles is ap- 

 proximately 24 feet per mile toward the south and toward the 

 west, the latter dip being caused mainly by the decrease in that 



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