6 NEW YORK STATE MUSEUM 



This ridge, barely above the present lake level at the north end, 

 rises toward the south at an average rate of 50 feet per mile to 1400 

 feet above it at the south side of the Ovid quadrangle. 



The higher eastern and western slopes are moderately steep, 

 ranging from 100 to 250 feet per mile, while the lower reach 400 

 to 500 feet per mile and nearly vertical cliffs extend for many 

 miles along the lake shores, in which there is a magnificent display 

 of the stratigraphy of the region; the numerous ravines and 

 gorges cut through the thin drift mantle that overspreads the ridge, 

 some of which show rock walls 100 to 200 feet in hight, afford 

 abundant opportunities for the collection of fossils. These condi- 

 tions have made this region a specially attractive one to geologists 

 and its stratigraphy and surface phenomena have been discussed by 

 several scientific writers among whom are Prof. James Hall in the 

 annual and final reports of the fourth geological district 1837 to 

 1842, and Dr D. F. Lincoln in a report on the geology of Seneca 

 county published in the 14th Report of the State Geologist of New 

 York, 1895. 



STRATIGRAPHY 



The following formations are represented on the map : 



Chemung sandstone 

 Prattsburg shale • 

 High Point sandstone 

 West Hill flags and shale 

 Grimes sandstone 

 Hatch shale and flags 

 Rhinestreet shale 

 Cashaqua shale 

 West River shale 

 Genundewa limestone horizon 

 1 Genesee shale 



Tully limestone 

 Moscow shale 

 Tichenor limestone 

 Ludlowville shale 

 Skaneateles shale 

 Cardiff shale 

 Marcellus shale 

 Onondaga limestone 

 Oriskany sandstone 



Devoniv 



Chautauquan 



Senecan. 



Erian, 



Ulsterian. . 

 Oriskanian . 



