MURPHREE'S VALLEY ; STRUCTURE. 33 



It is evident that there is not space enough on the south- 

 east side of the fault to contain the counterpart of the strata 

 on its northwestern side, in any form of fold that could be 

 assumed. That large portions of the strata on the south- 

 east side of the fault have gone down in it been engulfed or 

 folded under is evident. 



Their absence and the direct contact of the Cambrian 

 strata on the one side with Clinton or Subcarboniferons on 

 the other, indicate the position of the great fault. This 

 fault extends the whole length of the valley but is not 

 throughout of equal magnitude of displacement. Its 

 greatest depth is in that part of the valley where the 

 Cambrian limestone is exposed, above that towards the head 

 of the valley it gradually diminishes in depth. 



It is very generally believed that the structural features of 

 the Appalachian region have been, produced through the 

 agency of a force acting from the direction of the Atlantic 

 ocean, i. e. from the east and southeast, by which the strata 

 have been compressed into much less space than they 

 occupied in their original horizontal position. This 

 lessening of the area was accomplished by folds and 

 flexures and by the rupturing of the sharply bent strata and 

 the sliding of one portion bodily over another portion. An 

 examination of this region will show that in nine cases out 

 of ten, the folds when not symmetrical, have been lapped 

 over in the direction towards which the force was exerted, 

 and where faulting occurred, the overriding portions were 

 pushed or thrust up in the same direction, i. e. northwest. 

 In Murphree's Valley all this is reversed, and we find the 

 strata occupying such positions as they would normally 

 have assumed under the action of a compressing force acting 

 from the northwest, raising a fold, lapping it over towards the 

 southeast, and after faulting thrusting the northwestern half 

 of the broken fold in the same direction. 



Inasmuch as we have no evidence of any compressing 

 force acting from this direction, we must explain the 

 peculiar structure of Murphee's Valley under the dynamic 

 conditions which obtain in other parts of the state. This 



