1884.] l^i [Stevenson. 



the chertj'^ beds of the Knox, which weather with a fretted surface, are 

 exposed along the southerly side as far eastward as the Saltville railroad. 



Northward from the fault of Walker mountain the sequence is regular 

 until, at a distance of about four miles, the 



Saltville Fault 



is readied. This was designated in the writer's previous memoir as the 

 fault of the North Fork of Ilolston, the name {ipplied to it by Prof. Lesley. 

 That observer having touched this fault only near Saltville, naturally 

 applied to it the name of the river by which it is crossed more than once 

 in that neighborhood. But, as will be shown, that name is misleading, 

 and "Saltville" is much preferable, as the line of the fault passes through 

 the widely known village of that name. 



This fault is crossed by the Bristol and Stone Gap Railroad grade within 

 a few rods north from the Rich Valle}'^ road and only a little way south 

 from the deep cut on Wolf Run summit. Its place is wrongly indicated 

 on the writer's earlier map, on which it should be very nearly where the 

 Walker Mountain fault has been placed. The course of the fault eastward 

 from the railroad is almost straight to Saltville on the border of Smyth 

 county. It passes through that village not many yards from the salt-shaft : 

 it lies between the Broad ford road and the river ; is crossed by the latter 

 probably twice within six miles east from Saltville, and is again crossed 

 or touched by it at ten miles from Saltville ; it is crossed by COve creek at 

 a little way north from I. H. Buchanan's house and by Lick creek at only 

 a little way north from the Saltville and Sharon Springs road. Beyond 

 ten miles eastward from Saltville, that road lies south from the fault. 



The North forkof Holston rises in Bland county, follows a very serpen- 

 tine course through Knox and Trenton limestones for fifteen or twenty 

 miles, and touches the Saltville fault at ten miles east from Saltville. 

 Thence until very near the Broadford, six miles from Saltville, the river is 

 south from the fault, but in the next three miles the fault is crossed cer- 

 tainly more than once. At somewhat more than three miles east from 

 Saltville ihe river crosses to the northerly side of the fault, finally. Within 

 Washington and Scott counties the river bed and the fault are from two 

 to five miles apart, with the clumsy Brushy mountain occupying the 

 interval. In a distance of seventy or eighty miles the North fork of Hol- 

 ston crosses or touches the Saltville fault not more than four times, all of 

 them within a space of eight miles ; while during the rest of its flow 

 through Bland, Smyth, Washington and Scott counties it is from one to 

 five miles either north or south from the line of fracture. Its course 

 seems to be dependent on neither the fault nor the character of the rocks 

 for it is serpentine alike through the yielding limestones of the Trenton, 

 the refractory sandstones of the Knox, the hard and soft limestones of the 

 Lower Carl)oniferous, the soft shales and hard sandstones of the Lower 

 Carboniferous, Devonian and Silurian. 



The relation of the Saltville fault to the Burk's Garden anticlinal of the 



PROC. AMEB. PHILOS. SOC. XXII. 118. P. PRINTED FEBRUARY 19, 1885. 



