STRATIGRAPHIC CLASSIFICATION DIASTROPHIC CRITERIA 419 



Judging from the distribution of succeeding deposits, this westerly tilt 

 of the Nashville dome seems to have been maintained to the close of 

 the Devonian, when the widely transgressing Chattanooga shale encircled 

 and possible spread over the whole dome. 



That the vertical movements of the two domes of the Cincinnati 

 geanticline were not uniform or alike — in other words, that the move- 

 ments which affected the two domes often differed in direction and 

 volume — will be apparent on comparing the above brief accounts. Thus, 

 while alternate east and west tilting of the Nashville dome is clearly 

 indicated in the closing stage of the Stones Eiver and during the Low- 

 ville by the absence of the latter on the west side and the absence of 

 the Carter limestone on the east, no corresponding differential move- 

 ments of the Cincinnati dome are suggested by the areal distribution 

 of the equivalent deposits in Kentucky. Again, whole formations present 

 in Kentucky, as, for instance, the Wilmore and the Eden, are absent 

 in middle Tennessee, such facts being interpreted as indicating relative 

 elevation of the Nashville dome, while subsidence of the Cincinnati 

 dome was in progress. Finally, though the submergences which encircled 

 either of the two domes are usually common to and alike in both, as the 

 Hermitage, Bigby, Catheys, and less clearly the Maysville or Leipers, the 

 submergences which affected only a part of the circumference of either 

 are usually different in the direction of the tilt. Thus, while the Cin- 

 cinnati dome was tilted to the south or southwest during deposition of the 

 Flanagan and Perry ville limestones, the Nashville dome was tilted to the 

 northeast. 



Oscillations in the Mississippi Valley. — Essentially the same kind of 

 differential movements affected the Ozark, Arbuckle, and Wisconsin 

 uplifts during the Canadian and Ordovician. In these instances, how- 

 ever, it is much more difficult to establish the stratigraphic relations of 

 the beds on opposite sides of the uplifts. In the case of the domes of 

 the Cincinnati geanticline the same formations are found on both uplifts, 

 and the varying movements of the domes have so arranged the deposits 

 that the sedimentary record in the one supplements that in the other 

 and establishes a succession that could not be fully worked out from 

 either. If we did not know that the Lowville (Tyrone) limestone rests 

 on the Carter limestone at Highbridge, Kentucky, it would have been 

 difficult to prove to the satisfaction of stratigraphers that the beds 

 resting on the Lebanon limestone on the east side of the Nashville dome 

 are younger than the Carter limestone, which follows the Lebanon on 

 the west side. The faunal evidence, it is true, suggested the absence of 



