GEOLOGY OF THE W ATKINS AND ELM IRA QUADRANGLES J 



Loxonema noe, Bactrites aciculum, Manti- 

 coceras pattersoni, Goniphoceras cf. manes, 

 Palaeotrochus praecursor, P 1 e u r o t o m a r i a 

 i t y 1 u s , P a 1 a e o n e i 1 o muta, A t r y p a reticularis, 

 C h o n e t e s s c i t u 1 u s , Li'ngula s p a t u 1 a t a . 



Cashaqua shale 



In the Naples valley at the base of these very characteristic beds 

 there are 45 feet of shales, the larger part of which is black and 

 bituminous. They constitute a distinct element in the succession 

 there and have been designated as the Middlesex shale. Westward 

 from Naples the formation becomes more bituminous and thinner 

 and the lighter shales disappear. On the shore of Lake Erie, as 

 exposed at the mouth of Pike creek, it is a band of black slat)' shale 

 6 feet thick. Eastward from the Naples valley in Italy Hollow and 

 on the shores of Keuka lake this division becomes less bituminous 

 and more argillaceous and on this quadrangle its position is occupied 

 by shales having the character of the typical Cashaqua shale at 

 Naples and in the Genesee valley. The beds also contain, though in 

 very small numbers, the fossils of those shales. The Middlesex 

 shales therefore do not appear on this map. 



The Cashaqua shale here attains a total thickness of 207 feet. At 

 its base there are about 30 feet of soft argillaceous shale, dark bluish 

 gray or olive in color, in which there are a few thin seams of black 

 shale and an abundance of small calcareous concretions. Toward 

 the top are 2 or 3 layers of evenly bedded bluish gray sandstone 4 to 

 10 inches thick. This lower horizon is finely exposed along the lake 

 shore and in the rock cut of the Northern Central Railroad, 443 to 

 475 feet A. T. between Watkins and Salt Point, where the following 

 fossils have been found : Manticoceras sp., Bactrites a c i c u - 

 1 u m , Orthoceras sp., S t y 1 i o 1 i n a f i s s u r e 1 1 a , P a 1 a e - 

 o n e i 1 o f i 1 o s a , J } t e r o c h a e 11 i a f r a g i 1 i s , Para- 

 cardium d o r i s , Bu c h i o 1 a cf . s c a b r o s a . All these 

 fossils are rare. These lower shales are overlain by an arenaceous 

 band which, at the lowest rock exposure at the mouth of Watkins 

 Glen, is composed of a 5 inch sandstone overlain by 5 inches of dark 



