Stevenson.] « " [March 18, 



crushing and distortion are very much less than that observed near the 

 Kew Garden fault in Tazewell county, the Hunter valley fault in Russell, 

 or even the Max Meadows fault on the railroad. Where crossed by the 

 Wythe and Tazewell pike it shows dips of thirty to forty degrees in the 

 Lower Carboniferous, and forty to fifty-five degrees in the Knox limestones 

 at about equal distances from the line of faulting ; on the Dublin and 

 Pearisburg road, the dip is comparatively gentle and the succession of 

 Lower Silurian on top of Lower Carboniferous appears to be wholly con- 

 formable ; a similar condition exists on New river, where the dips in the 

 Umbral shale near the fault are only ten to fifteen degrees, while in the 

 Vespertine further from the line the dip rises to fifty-five degrees. Here, 

 however, the rocks on the southerly side are disturbed, and the beds are 

 wrinkled for a mile or more. Near Tom's creek the greater disturbance 

 is on the northerly side, where the Lower Carboniferous beds are almost 

 vertical, though dipping toward the fault, while the Knox limestones are 

 dipping much less sharply in the same general direction. 



The structure between the Walker Mountain and Saltville faults is much 

 less complicated than that of the next block southward. The Vespertine 

 Coal group is exposed continuously on the northerly side of the former 

 fault from eastern Smyth to beyond the centre of Montgomery county, 

 and the course of the fault is -so little ofi the strike of the beds that the 

 thickness of the overlying Umbral shales shows very little change from 

 Wythe county eastward. Big Walker mountain is a Medina ridge sepa- 

 rated by a Clinton and Hamilton valley from Little Walker mountain, 

 an Upper Devonian ridge with Lower Carboniferous sandstones and 

 shales on its southerly slope. The dip throughout, or nearly so, is south 

 of south-east at from ten to sixty degrees. Petty wrinkles occur in the 

 shales, but the only material interruption of the dip on Big Walker is near 

 the Tazewell pike, where at barely five or six miles from the Smyth county 

 line an anticlinal evidently has its origin. This rapidly increases eastward 

 and soon causes a considerable southward deflection in the Medina out- 

 crop or. crest of Big Walker mountain. The axis must be cut several 

 times by Walker's creek, which flows on Knox limestone along the 

 northerly foot of the mountain ; and the fold shows no material decrease 

 until beyond the line of Bland county ; but thence to New River gap, the 

 Medina of Walker mountain gradually approaches the Saltville fault. 

 The interval between that fault and the Medina opposite Seddon is fully 

 three miles, but at New River gap it is barely one mile. 



The dips on the northerly side of Big Walker are comparatively gentle 

 except for a few miles on each side of the New River gap ; and it is worthy 

 of notice in this connection that the dips throughout Big and Little Walker 

 along the New river are much more abrupt than at any other localities. 

 Possibly the approach of the Medina outcrop to the Saltville fault may be 

 due as much to a thrust as to diminished strength of the Walker Creek 

 anticlinal. 



