102 



STRUCTURAL GEOLOGY OF NORTH AMERICA 



MAYNARDVILLE QUADRANGLE 



KNOXVILLE QUADRANGLE 



Northwest of 

 Wallens Ridge 



5 



Southeast of 

 Wallens Ridge 



Northwest of 

 Bays Mountain 



I 



Chilhowee 

 Mountain 



■1-yzv-v":"---* Chattanooga" shale \ -_-_j- l = ~ r -_ - r '-~- - - -~~ - = ~ ~ ~~~ ~~~~ """ "" 



S^^agjb»^£ ^evrer"j jjiii ~£?&S^%£ 





•. ! .-. : .v. -:.'-..fpllico sandstone"; •„•: 







2 * 



3 3 

 <: 



4.t; 



*■» 



5 Co 



Conglomerate locally 



Fig. 8.5. Stratigraphic diagram of Middle and Upper Ordovician and Silurian rocks of Valley and Ridge 

 province of eastern Tennessee. After P. B. King, 1950a. 



of the strata below the thrust sheet are in the same position as those of 

 the thrust sheet, but in detail the contacts are discontinuous against the 

 thrust, and in other areas a complete lack of coincidence occurs. This 

 suggests three episodes of compressional orogeny, perhaps almost in 

 continuous succession: first the folding and erosion of the strata in front 

 of the thrust and, perhaps, the early development of the thrust itself; 

 then the movement of the great sheet out over the folded and eroded 

 terrane; and third, further folding, involving both the thrust sheet and 

 the underlying strata. Immediate waste products of the folds and thrusts 

 which have been overridden and preserved, or which partially bury the 



structures, are not apparent. Such waste products in the form of coarse 

 piedmont elastics are present in some of the Rocky Mountain thrusts and 

 serve to date the various stages of deformation. Regarding the Rome 

 thrust, however, all three closely related episodes of deformation are 

 younger than the Lower Pennsylvanian Pottsville, which is involved in 

 the deformation. 



Another conspicuous structural division of the Valley and Ridge 

 province of the southern Appalachians is the zone of shallow, flat thrust 

 sheets, like the Rome, along its eastern margin. These are largely part 

 of the Rlue Ridge province, and involve Cambrian and Ordovician strata, 



