CONEMAUGH FORMATION IN OHIO 193 



whole of the Conemaugh. Mr Bead found the Pittsburg coal bed 145 

 feet above the Ames limestone and the latter 112 feet above the Cam- 

 bridge, which is only 72 feet above the Upper Freeport, giving thus a 

 thickness of 329 feet for the Conemaugh. The Brush Creek coal bed 

 and the Mahoning limestone are present in his sections, the latter being 

 sometimes only an ore bed.* 



Athens county is south from Perry and Morgan and east from Hock- 

 ing. Professor Andrews finds the Ames limestone 138 to 145 feet below 

 the Pittsburg (Federal Creek) coal and the Cambridge limestone at 

 85 to 90 feet lower, with, at some localities, the intermediate Ewing 

 limestone at 50 feet above the Cambridge. The Ames is 180 to 190 feet 

 above the Upper Freeport (Baileys run) coal bed, practically the same 

 as in Read's Sunday Creek section in Morgan county, so that the Cone- 

 maugh in all is about 330 feet thick. Limestones, not wholly persistent, 

 are 4 to 6 and 75 feet below the Pittsburg. The Harlem coal seems 

 to be persistent at about 25 feet below the Ames and at times underlies a 

 sandy black fossiliferous shale. The interval between Ames and Cam- 

 bridge is fully exposed near Athens, midway in the county, where, aside 

 from the Harlem coal and Ewing limestone, it contains only shale and 

 laminated sandstone, 34 feet of the latter resting on the Cambridge lime- 

 stone, the Cowrun sandstone. The Cambridge limestone is double in the 

 northern part of the county and the interval between the divisions is at 

 times more than 25 feet; but the lower division, underlying the Anderson 

 coal bed, disappears midway in the county, to reappear irregularly 

 farther south. In this region the upper division is persistent. Occa- 

 sionally one or both are flinty, but the upper is sometimes pure enough to 

 yield good lime. The interval between Ames and Pittsburg in the eastern 

 township of Ames is 140 feet, according to Andrews, but Mr Love joy 

 finds it 171 farther west, where the section shows great variation. A 

 coal and limestone — perhaps the Jeffers — are sometimes present at 54 

 to 57 feet; a white limestone underlies the Pittsburg at one locality, but 

 at another, one finds 28 feet of red shale; while at a third, heavy sand- 

 stone fills the whole interval to the Ames. 



On the Morgan- Athens border the Ames is 170 feet below the Pitts- 

 burg, and in Ames township of the latter it is 115 feet above the Cam- 

 bridge limestone, evidently the Upper Cambridge, for it underlies 33 feet 

 of sandy shale, representing the Cowrun sandstone. Here, at 6 miles 

 east from the line of Washington county, Professor Bownocker's measure- 

 ments and oil-well records make the Cambridge limestone 285 feet below 



* M. C. Read : Vol. iii, pp. 679, 705. 

 E. Orton : Vol. v, pp. 100-101, 920. 



XVI — Bull. Geol. Soc. Am.. Vol. 17. 1905 



