CORRELATION OF ALLEGHENY FORMATION 73 



The Vanport limestone In Pennsylvania, Ferriferous, Vanport ; in 



I. C. White, 1878. Ohio, Ferriferous, Baird, Coshocton marble ; 



in Kentucky, Ferriferous ; in West Virginia, 

 apparently wanting. 



This is in some respects the most remarkable member of the formation ; 

 it has not been observed in the first and second bituminous basins of 

 Pennsylvania, but a limestone of similar character has been reported from 

 the first basin southward in Maryland, which, however, may prove to be 

 at the Putnam Hill horizon. This bed has been observed only at one 

 locality in the area immediately west from Chestnut Hill, and there is 

 much room for doubt respecting its existence in the counties south from 

 the Ohio and Kiskiminetas except near the former river toward the West 

 Virginia line; but north from those rivers it is persistent almost to the 

 northern outcrop and to the Ohio line, becoming somewhat irregular 

 toward the north, where it is replaced sometimes by cherty limestone or 

 sandstone and seems to project, finger like, northward from the main 

 mass. It practically disappears within a few miles west from the Ohio 

 line, though it has been recognized by Professor Orton at several places 

 beyond. In Pennsylvania it usually underlies an iron ore which in the 

 earlier days was the source of supply for many furnaces. It reappears 

 in central Ohio as the Black marble of Coshoction county, and thence 

 southward it is followed easily as the Baird ore and limestone, to which 

 E. B. Andrews applied the name Ferriferous limestone, but without any 

 reference to the Pennsylvania bed. It is persistent southward in Ken- 

 tucky into Elliott county and appears occasionally in Morgan county 

 beyond; but eastwardly it disappears in Boyd and Lawrence . counties be- 

 fore reaching the West Virginia line. It belongs chiefly to the western 

 side of the basin. Within Pennsylvania and northern Ohio it carries a 

 marine fauna, but in southern Ohio and Kentucky it seems to be non- 

 fossiliferous. 



The Clarion coal bed of H. D. Kogers is a double bed, as was demon- 

 strated by Doctor H. M. Chance, but the splits are recognizable as such 

 in a very small area, so that they have received distinct names. The 

 upper split is: 



The Scrubgrass coal bed Sulphur, Ferriferous, Upper Clarion, Canfield, 



I. C. White, 1879. at various localities in Pennsylvania and 



Ohio. 



This bed occurs in western Pennsylvania and in much of Ohio directly 

 beloAv the Vanport limestone or separated from it by at most 10 feet. It 

 is of uncertain occurrence and rarely is thick enough to be mined even 

 for local supply. 



