826 



/. A. BOWNOCKER 



one of the earliest blast furnaces in the state relied on this ore. 

 In composition the rock is calcareous, and at one point becomes 

 the purest rock of this type in the state. 



Northward, under cover, the rock undergoes notable changes, 

 the result being that it closely resembles the overlying Niagara. 

 It is in the central portion of the state, however, that the greatest 

 change is found. Instead of a well-marked limestone, there is 

 found in its place shales of different colors and composition and 

 a conspicuous sandstone ; the latter the repository for the great 

 reservoirs of gas in Fairfield, Hocking, Licking and Knox coun- 

 ties. In northern Vinton county a pool of oil also has lately been 

 found in it, and one well has been secured in Perry county. 



The relations of these beds to the overlying Niagara are shown 

 in the following partial log of a well on the Bauer farm near Sugar 

 Grove. Samples of drillings below the Niagara were taken by 

 the writer. 



Berea grit ------ 



top at 

 bottom at 



Corniferous, Helderberg, 



and Niagara limestones - 



f Shales, light chocolate-colored. 

 Little lime - 

 Shales, green and chocolate-colored, 

 Clinton -l the latter fossiliferous. Some lime 

 Shales, green and chocolate-colored. 

 Much lime -.-.-. 



620 feet 

 645 



top at 1,430 

 bottom at 2,132 

 top at 2,132 

 bottom at 2,168 

 top at 2,168 

 bottom at 2,199 

 top at 2,199 

 bottom at 2,236 

 2,236 



(_ Clinton sand at 



Generally when the gas sand has been penetrated to a depth 

 of from 10 to 15 feet the drill is stopped, and consequently data 

 farther down are less abundant. In western Ohio the basal portion 

 of the Niagara is commonly occupied by shales, 1 but northward 

 and eastward this member contracts. In central Ohio it consists 

 of shales and thin beds of limestone, and the bottom of these 

 is regarded as the line of junction of the Niagara and the Clinton. 



The following skeleton record of a well on the Spire farm near 

 Sugar Grove shows the position of the Medina as well as the 

 Clinton : 



1 Ibid., pp. 1 1- 1 3. 



