1881.] ^^ * [Stevenson. 



line ; also where the Estillville and Stony creek road crosses Copper creek ; 

 and in the Clinch river gap. This fault continues into Tennessee ; it brings 

 up the base of the upper division of the Knox group against the higher 

 beds of the Trenton and Nashville group. Moccasin ridge, lying between 

 Copper and Moccasin creeks, and owing its existence to the Copper creek 

 fault, is a monoclinal with a dip thx'oughout of little more than 30 degrees. 

 It consists of rocks belonging to the Lower Silurian. Moccasin valley, 

 eroded by the creek of the same name, separates Moccasin ridge from 

 Clinch mountain, in which one finds a continuation of the series. The 

 upper shales of No. Ill are shown on the northerly side, while the Medina 

 sandstone forms the crest. Southerly dips continue beyond the crest of 

 Clinch mountain, across the Poor valley and to the southerly side of Brushy 

 mountain, where one reaches the 



Fault of the North, Fork of Holston. — Along the line of the Bristol 

 railroad, this fault is reached at about three miles from the river, the dis- 

 tance being measured along the shortest line ; but it is at somewhat more 

 than six miles by the railroad. Near the Tennessee line, it is little more 

 than one mile from the river at the mouth of Moccasin creek. It extends 

 for a long distance toward the north-east and reaches into Tennessee. This 

 fault is not inferior to tlie Hunter Valley fault, for it brings up the middle 

 division of the Knox group against the very top of the Lower Carbonifer. 

 ous. But it shows none of the complex structure seen along the Hunter 

 Valley fault. Wherever examined, the Lower Carboniferous rocks dip to- 

 ward the fault and are not turned up near the line of fracture. There is, 

 however, some crumpling at a little w^ay from the break. A synclinal was 

 seen on the North Fork of Holston at but a little way above the mouth of 

 Moccasin creek, and an anticlinal is described at a little way further south- 

 east. The same condition was seen along the railroad line beyond North 

 Fork of Holston. Abrupt changes of dip occur in the Lower Carbonifer- 

 ous rocks along several lines in Brushy mountain. 



The Walker Mountain fault follows the northerly side of that mountain 

 and brings up the base of the Knox group so as to be in contact with the 

 top of the Trenton and Nashville group. This fault extends for at least 

 eight miles. No study of structure was made between Walker mountain 

 and Bristol, where the line of section ended. In all probability, however, 

 a small fault occurs in that interval, for the chertj'' beds at the top of the 

 Knox group occur in the immediate vicinity of Bristol. 



The extent of the several faults is approximately as follows : 



1. Fault of Poor valley 2400' 



2. Wallen Valley fault 2800' 



3. Pattonsville fault 500' 



4. Hunter Valley fault or Clinch Biver uplift 8000' 



5. Copper creek fault 3000' 



6. Holston fault 7500' 



7. Fault of Walker mountain 8000' 



The Holston and Hunter Valley faults were much greater originally, for 



PKOC. AMER. PHILOS. SOC. XIX. 108. 2c. PRINTED FEBRUARY 23, 1881. 



