154 J. J. STEVENSON CARBONIFEROUS OF APPALACHIAN BASIN 



CONEMAUGH FORMATION 

 CORRELATION 



The southern limit of the Conemaugh can not be determined in the 

 present state of our knowledge, but there seems to be little room for 

 doubt that the lower members of the formation are present as far south 

 as Pike county of Kentucky, southwest from Mingo county of West 

 Virginia. Owing to the absence of any beds of coal, limestone, or iron 

 ore possessing economic value in any considerable area, the Conemaugh 

 has been regarded as "barren," but its coal and some other horizons 

 prove to be quite as persistent as those of the other formations and its 

 variations are quite as interesting as those of the Pottsville. The interval 

 between the Upper Freeport and the Pittsburg coal bed decreases west- 

 ward from about 600 feet along the northerly outcrop in Pennsylvania 

 to about 300 feet along the western outcrop in Ohio and to somewhat less 

 in Kentucky, if one may draw conclusion from the portion remaining in 

 that state. 



The noteworthy horizons in the Conemaugh are numerous, but, owing 

 to abrupt variations in character and thickness of the detrital beds, there 

 has been some confusion respecting the relations. The succession in de- 

 scending order is : 



Little Pittsburg limestone. 

 Little Pittsburg coal bed. 

 Little Clarksburg coal bed. 

 Morgantown sandstone. 

 Elk Lick coal bed. 

 Washington reds. 

 Ames limestone. 

 Harlem coal bed. 

 Pittsburg reds. 

 Barton coal bed. 

 Cowrun sandstone. 

 Anderson coal bed. 

 Cambridge limestone. 

 Buffalo sandstone. 

 Brush Creek limestone. 

 Brush Creek coal bed. 

 Upper Mahoning sandstone. 

 Gallitzin coal bed. 

 Mahoning limestone. 

 Lower Mahoning sandstone. 

 Uffington shales. 



The Pittsburg limestone of H. 1). Eogers consists of one or more beds 

 within an interval of about 25 feet below the Pittsburg coal bed, the 



