56 J. J. STEVENSON CAEBONIFEEOUS OP APPALACHIAN BASIN 



mile away it is 2 feet 1 inch thick and with but 2 inches of slate. The 

 main division is very iiniform, though often cut out badly by descent 

 of the sandstone roof, and so sometimes distorted by clay-veins. 



Southwestwardly the limestones increase as rapidly as in the Blairs- 

 ville basin, for within a few miles the Benwood limestone is about 80 

 feet thick, with, directly under it, a richly carbonaceous shale repre- 

 senting the Upper Sewickley. The Waynesburg coal bed is shown far- 

 ther south, near the Youghiogheny, thick and 25 feet above 7 feet of 

 Waynesburg limestone. The Benwood is 65 and the Fishpot is 20 feet 

 thick on the Youghiogheny. The Upper Sewickley coal bed, directly 

 under the Benwood, is 5 inches thick and separated by the thinly bedded 

 Sewickley sandstone from the limestone below. The Eedstone coal bed 

 is 60 feet above the Pittsburg and its ferruginous limestone is 6 feet 

 thick. Between the Youghiogheny and the Monongahela an imperfect 

 measurement gave 260 feet as the interval from Waynesburg to Pitts- 

 burg. The Waynesburg, Uniontown, and Upper Sewickley are all very 

 thin, but the Eedstone is often 3 feet. The last bed is much cut by clay 

 veins, which bear no relation to disturbances in coal beds above or below. 

 Such clay veins are characteristic of the Redstone and explain its absence 

 from many records and sections. In this space between the rivers the 

 Fishpot and Redstone limestones become very irregular at and in many 

 places are represented only by nodules.* 



Passing over into Fayette county, one finds the intervals increasing 

 rapidly, though showing some irregularity. Between the Youghiogheny 

 and the Monongahela, all members of the section except the Lower 

 Sewickley coal bed are exposed frequently. The Waynesburg coal bed is 

 sometimes 4 feet thick, the Upper Sewickley is from 3 inches to 30 inches 

 thick, and the Redstone 3 to 4 feet, but the Little Wa5Tiesburg and the 

 Uniontown are very thin. The limestones are important, the Benwood 

 occasionally becoming 90 and the Fishpot 35 feet thick. The interval 

 from Waynesburg to Pittsburg is 330 feet in Franklin township, where 

 the Upper Sewickley is 118 feet above the latter bed. The Redstone 

 coal bed is 25 to 40 feet above the Pittsburg and the Redstone limestone 

 is somewhat indefinite. Near Brownsville, on the Monongahela, the 

 Waynesburg is 345 to 360 feet above the Pittsburg and the Upper 

 Sewickley is only 6 inches thick. In this direction the Benwood lime- 

 stone becomes broken by a sandstone which at Brownsville is 20 feet 

 thick. 



* J. J. Stevenson: (K 2), pp. 329, 335, 336, 339, 351, 352, 353, 361, 362, 363, 364. 

 R. W. Stone : U. S. Geol. Survey folios. Elders ridge, p. 6. 



