204 J. J. STEVENSON CARBONIFEROUS OF APPALACHIAN BASIN 



The Buffalo, on the other hand, is persistent though variable, sometimes 

 replacing the underlying shales and encroaching upon the place of the 

 Upper Mahoning. Its top is from 382 to 387 in Monongalia, 380 to 407 

 in Marion, the bottom being from 395 to 430 in the former and from 406 

 to 457 in the latter, the thickness of the sandstone varying from 5 to 50 

 feet. The Mahoning interval is more variable than the Buffalo. 

 Typically it has two sandstone plates, upper and lower, separated by 

 shales ; the lower is the more persistent, the upper being replaced by shale 

 very frequently; but in some localities the whole interval is occupied by 

 massive sandstone. Ordinarily one finds between the sandstone and the 

 Upper Freeport from 10 to 40 feet of shales, but occasionally the shale is 

 replaced and the sandstone rests directly on the coal bed. The top of 

 the Mahoning sandstone in Monongalia is from 421 to 475 feet below 

 the Pittsburg, but from 436 to 515 feet in Marion ; the bottom in Monon- 

 galia is from 515 to 521, in Marion from 538 to 578 feet, in the last case 

 extending downward to the Upper Freeport. 



The Anderson coal horizon is marked by a coal bed at 375 feet, re- 

 ported in a Monongalia well, and a coal at 275 in a Marion well is very 

 near the place of the Harlem. 



The red beds in northern Monongalia are immediately under the Mor- 

 gantown sandstone, 245 or 265 feet below the Pittsburg coal, to 330 or 

 340 feet, thus including the "Big Bed" of Ohio overlying the Ames and 

 the Pittsburg reds underlying that limestone. In southern Monongalia 

 and in Marion red beds occur in some portion of this interval at almost 

 all localities and occasionally higher beds appear — in one well at 86 to 

 111 feet, in two others at 127 to 230 feet, and in a third a great bed is at 

 161 to 326, replacing the Morgantown sandstone. The lowest bed re- 

 corded is in a well on the Marion-Monongalia border 341 to 381 feet 

 below the Pittsburg. This is wanting in other records.* 



In western Marion, on the border of Wetzel county, there appears at 

 one locality to be only shale for 603 feet below the Pittsburg to the Butler 

 or Upper Freeport sandstone, or possibly the (Lower) Freeport sand- 

 stone. Crossing over into Wetzel county, one finds, at 10 miles south- 

 west, the only sandstone at 480 to 510 feet, while midway between the 

 wells this sandstone is at 500 to 515 feet, the Lower Mahoning. Bight 

 or 10 miles northward the sandstones are at 406 to 446 and 470 to 548 

 feet, and at 10 miles northwest, on the Marshall border, the only sand- 

 stone is at 509 to 569, with the Lower Freeport coal bed at 575, the place 

 of the Upper Freeport in eastern Monongalia and Marion. The sand- 



* I. C. White : Geology of West Virginia, Monongalia county, vol. i, pp. 234-236 ; vol. 

 \a, p. 134 ; vol. ii, pp. 230, 269 ; Marion county, vol. i, pp. 238, 240, 242, 245, 247, 348. 



