304 



GEOLOGY OF OHIO, 



The sandrock A is but little broken, the layers all retaining their 

 proper positions. The shales B are somewhat distorted, but the laminae 

 are nearly horizontal. C is the crushed and pulverized debris of shale, 

 showing that the whole mass of the rock A has been pushed bodily from 

 its position, grinding up the material beneath it, till it has taken on the 

 appearance of glacial drift, but is composed wholly of the debris of the 

 rocks below A. The mass A is some eight to ten feet thick, and is ex- 

 posed for several rods in the bluff, with no indications that it has been 

 moved from its native bed, except the character of the material beneath 

 it. 



At Cole's quarry, one and a half miles south-east of Norwalk, the Berea 

 is only two hundred and five feet above the Lake, and in its position and 

 surroundings affords a remarkable illustration of the superficial disturb- 

 ances which prevail over a large part of the county. The rock is in thin 

 evenly-bedded layers, dipping 27° south-easterly, the line of strike being 

 north 22° east. Directly north some fifteen or twenty rode, and on the oppo- 

 site side of a small stream, the black shale is in position at the same level ; 

 the strata horizontal and undisturbed. About two rods north, and a little 

 east of the quarry, the Bedford shales are exposed, dipping south about 

 27°. ' North from the last, and on the opposite side of the stream, a bluff, 

 twenty-five feet high, shows a mixture of Erie and Bedford shales. The 

 following sketch will show the relations of these different rocks : 



Bluffs at Colk's Quarry, Norwalk. 



A— Quarry in Berea grit, dip 27°. 

 BB — Black shale, horizontal. 

 C— Beflford shales, dip 27°. 



D— Blnff of Brie shales much disturbed, dip irregular, with the '• turtle-baoks " of the Bedford 

 shales as in the figure below. 



