450 INDEX TO THE STRATIGRAPHY OF NORTH AMERICA. 



Of these the last tliree are lower Pottsville (equivalent to the Lee) ; and the Dotson sand- 

 stone is correlated by both I. C. Wliite and the present writer with the Nuttall sandstone. 

 The 60 feet of shales in the lower part of the Dotson, together with the BearwaUow and Dismal, 

 therefore represent the Sewell, that is, the middle PottsTille. The Dotson sandstone, supposed 

 to correspond to the Sharon conglomerate member, goes, along with the Sequoyah and Tellowa, 

 which represent the Kanawha, into the upper Pottsville, the Sequoyah being in the lower half 

 of that formation. 



In the two contiguous quadrangles, Bristol and EstUlviUe, lying in the Big Stone Gap field, 

 the Peimsylvanian syncline between the Pine Mountain fault and the eastern edge of the coal 

 field contains, according to Campbell, the following: 



Harlan sandstone, 880 feet, sandstones, conglomerates and coals. [Not present in the Bristol quadrangle.] 

 Wise formation, 1,260 feet, shales, sandstones, and coals, with several thin marine limestones. [Only 100 feet 

 present in Bristol quadrangle, the rest of the formation being eroded away.] 

 Gladeville sandstone, 100-120 feet, conglomeratic sandstones, between coals. 

 Norton formation, 1,200-1,270 feet, shales, sandstones, and important coals. 

 Lee formation, 1,240-1,530 feet, sandstones, conglomerates, shales, and few coals. 



In this region, and on to the Tennessee line, the coals of the lower Pottsville are so unim- 

 portant and the sandstones so dominant that all are mapped in one formation, the Lee, which 

 includes everything to the top of the Raleigh sandstone of the Tazewell quadrangle.'^ 



Stevenson ''^^ places the horizon of the Sharon conglomerate member and of its supposed 

 southern representative, the NuttaU sandstone, in the Norton formation, at 800 or '900 feet 

 below the Gladeville sandstone, the latter being identified by him as the sandstone just under 

 the Upper Mercer coal on the west side of the coal field and therefore near the top of the upper 

 Pottsville. On the other hand, the writer would place the Gladeville at or very little above 

 the horizon of the Nuttall sandstone, making the Norton formation essentially equivalent to 

 the SeweU — that is, the middle Pottsville — while the Gladeville itself, followed by the Wise and 

 over 300 feet of the Harlan, which are found to contain Kanawha floras, are regarded by him 

 as upper Pottsville. The horizon of the Homewood sandstone member, the top member of the 

 upper Pottsville, is not yet fixed in the Harlan sandstone. The topmost beds in the "Flat^ 

 woods" of the region near Elkhorn, Ky., are put by the writer in the Harlan, the Flatwoods 

 coal itself being of Kanawha age instead of representing the Pittsburg bed, as was formerly 

 believed. 



The greater part of the Cumberland field, to the southwest of the Big Stone Gap coal field, 

 has been studied by Asliley and Glenn," whose work unfortunately fails to join with complete- 

 ness Campbell's work, just cited, or Keith's, farther south. The formations described are as 

 follows, those above the Lee being differentiated so as most satisfactorily to map the coal 

 groups: 



Bryson formation, 300 feet, sandstones, shales, and thin coals above Red Spring coal. 



Hignite formation, 440-450 feet, sandstones, shales, and coals, down to lower Hignite coal. 



Catron formation, 280-450 feet, shales, sandstones, local conglomerates, and numerous coals above Poplar Lick coal. 



Mingo formation, 950 feet, shales, sandstones, and good coals above the Bennett's Fork coal. 



Hance formation, 600 feet, shales, sandstones, and numerous thin coals. 



Lee sandstone, 1,200-1,500 feet conglomerates and sandstones, with thin shales and coals. 



The lower Pottsville (Lee) appears to continue in unity from the EstiUville quadrangle; 

 the Hance and about lialf of the Mingo represent the SeweU, the Gladeville being provisionally 

 placed by both Ashley and White ''^^''' in the region of the Slater and Puckett sandstone members, 

 a little above the middle of the Mingo formation. The Catron and Hignite formations, which 

 contain Kanawha floras, together probably with the upper part of the Mingo and certainly with 

 the basal portion of the Bryson, are included by the writer in the upper Pottsville. The Bryson 

 which, capping the highest Icnobs and ridges is present only in the deepest synclines, is there 

 equal in part to the Harlan of the Big Stone Gap region. 



a For information concerning the intervening area see Stone, R. W., Bull. II. S. Geol. Sirrvey No. 316, 1907, 

 pp. 42, 55; Bull. 348, 1908. 



6 See same paper also for correlations with other regions. 



