62 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



A shale which is, perhaps, the equivalent of the Waverly is pi-esent in 

 northern Indiana in greater thickness than in Ohio, the thickness as reported 

 bj Phinney being 143 feet at South Bend, 215 feet at Elkhart, and 200 

 feet at Groshen.^ The formation occupying the base of the Waverly series 

 in southern Indiana is the Rockford (Groniatite) limestone. It ma}- not, 

 however, be the precise equivalent of the Waverly shale. 



Eastward from northern Ohio the Waverly shale changes from a blue- 

 gray to a red color. It is thought by Carll to be developed only in a 

 narrow belt in northeastern Ohio and northwestern Pennsylvania, and that 

 mainly under cover of later rock formations." 



Berea grit and shale (Catskiii?). — Tlie Bcrca gi'it, although but a few feet in 

 thickness, is oiae of the most persistent and easily recognized formations in 

 eastern Ohio and northwestern Pennsylvania. Concerning it Orton has 

 remarked: " Its persistence as a stratum is phenomenal. Seldom reaching 

 a thickness of 50 feet, its proved area in Ohio, above ground and below, is 

 scarcely less than 15,000 square miles, and beyond the boundaries of Ohio 

 it appears to extend with certainty and strength unbroken into at least four 

 adjacent States."^ The name is taken from Berea, in northern Ohio, where 

 it is extensively quarried. It constitutes the "Waverly quarry stone " of 

 southern Ohio. It has had considerable influence in producing cascades in 

 northern Ohio. In both the ex^josed and the covered portion it consists of 

 a sandstone of medium coarseness, which in northern Ohio includes a thin 

 pebble bed. 



Above the Berea grit is a dark shale 15 to 20 feet in thickness, which 

 has been reported by Orton to form a constant cover throughout its entire 

 extent in Ohio. It is usually sharply in contrast with the blue beds of the 

 overlying Cuyahoga shale, but from Cuyahoga County eastward the line 

 of separation is in places not easily traced. 



Cuyahoga shale (part of Pocono sandstone of Pennsylvania). Tllis fomiatioU, which lu 



Ohio has a thickness of 150 to 400 feet, receives the name Cuyahoga from 

 extensive outcrops along the Cuyahoga River. It constitutes the main 

 member of the Waverly series, though the Logan conglomerate of central 

 and southern Ohio rivals it in strength. It consists, in the main, of light- 



1 Eleventh Ann. Kept. U. S. Geol. Survey, Pt. 1, 1891, p. 638. 



^ Second Geol. Survey Pennsylvania, Rept. I', 1880, map, p. 92; discussion, pp. 96-97. 



' Geology of Ohio, Vol. VII, p. 28. 



