CONEMAUGH FORMATION IN OHIO 185 



olive shale. A thin coal bed rests on the Ames limestone at this place, 

 but elsewhere it is 20 feet above, with green and red shale between them. 

 It appears to be at the Elk Lick horizon. Nearer the Ohio river the 

 Harlem coal is immediately under the Ames, the Barton is at 50 to 60 

 feet below, and the Lower Mahoning is coarse and pebbly sandstone. 

 The interval between the Brush Creek and Upper Freeport varies from 

 35 to 69 feet between Irondale and the Ohio river, and the Mahoning 

 limestone (Gray limestone of Newberry) is present in most of the sec- 

 tions.* 



Southward in Jefferson county numerous direct measurements by 

 Newberry, Orton, and Newton show that the interval from the Ames 

 limestone to the Brush Creek coal varies within 16 miles from 199 to 230 

 feet, the least interval being at Steubenville, the most southerly meas- 

 urement. This interval is filled mostly by red and olive shale, but at 

 several localities a coal bed appears at 27 to 46 feet above the Brush 

 Creek, marking a horizon first seen in eastern Beaver of Pennsylvania. 

 The interval from Brush Creek to Upper Freeport varies along this line 

 from 37 to 85 feet. At 3 miles southeast from the northwest corner of 

 the county Professor Newberry found the Harlem coal immediately under 

 the Ames limestone and another coal bed at 114 feet lower, immediately 

 above an impure limestone, the Cambridge, at 118 feet. This, the An- 

 derson coal bed, underlies variegated shale, but 10 miles away toward 

 the southeast, in Brooke county of West Virginia, it is 100 feet below the 

 Ames and underlies the massive Cowrun sandstone, 40 feet thick. A 

 bed at the Barton horizon is noted at several localities 55 to 65 feet below 

 the Ames limestone. 



The interval from the Pittsburg coal bed to the Ames limestone varies 

 from 149 feet in northern Jefferson to 225 feet in the southern part of the 

 county. A limestone is usually seen at 1 to 25 feet below the Pittsburg; 

 a coal and limestone marking the Little Clarksburg horizon are exposed 

 occasionally in northern Jefferson, and at one locality cannel occurs at a 

 Little Pittsburg horizon 40 to 50 feet below the coal. The Elk Lick 

 horizon is marked by coal at many places 20 to 35 feet above the Ames ; 

 but the section shows much variation, the whole interval being occupied 

 at one place by blue and sandy shales to 180 feet above the Ames. Eed 

 beds are at several horizons, but, excepting those associated with the 

 Ames, they are thin and of uncertain occurrence. The interval from 

 Pittsburg to Upper Freeport is 498 feet in northern Jefferson, 493 at 



* This is the Brush Creek limestone of volume v. 



