SOUTHERN AND CENTRAL APPALACHIANS 



101 



NORTHWESTERN 

 FACIES 



CENTRAL 

 FACIES 



SOUTHEASTERN 

 FACIES 



SOUTHWEST 

 VIRGINIA 



Copper Ridge dolomite 



dolomite 



Conococheogue limestone 



-2000 



_ LJ 



— ' — '—^ * — Pumpkin Valley shale znz^z 



-1500 



Ul 



1000 < 

 o 

 if) 



-500 



< 

 o 



h- 



rr 



UJ 

 > 



Rome 



formation 



Fig. 8.4. Middle and Upper Cambrian sedimentary rocks of eastern Tennessee and southwestern Virginia. 

 After Rogers, 1953. 



that are convex toward the ocean. The southern salient is principally in 

 Tennessee and southeastern Kentucky (see Tectonic Map of the United 

 States), and the northern salient is in central Pennsylvania. They are 

 about 400 miles apart. Keith points out two other salients in the northern 

 Appalachians which will be described later. 



Structural Characteristics in Alabama, Georgia, and Tennessee 



If the Tectonic Map of the United States is studied, it will be seen that 

 the southern half of the Valley and Ridge province is characterized by 

 thrust faults, whereas the northern half is chiefly one of long parallel 

 anticlines and synclines. In the southern part, the thrust sheets are 

 stacked in imbricate fashion on top of each other, and in eastern Ten- 

 nessee a succession of nine such sheets has been mapped. Some of the 

 thrust sheets carry almost the entire Paleozoic succession; others du- 

 plicate the lower Paleozoic succession only. Precambrian rocks have 



nowhere in the belt been exposed as the result of thrusting and erosion. 



The belt is made up almost entirely of thrust sheets in Tennessee, but 

 southward, especially along the northwest margin, the beds are cast into a 

 long anticline (Sequatchie) and syncline (Coalburg), which extend from 

 central Tennessee almost to the Cretaceous cover in Alabama. Also along 

 the southeast side of the belt in northwestern Georgia, a number of folds 

 are evident. They occur in a conspicuous embayment of the Blue Ridge 

 front. 



The nature of the thrusts and folds is illustrated in sections 1 to 4 and 

 8 to 12 of Figs. 8.11 to 8.17. The location of the sections is given on the 

 index map of Fig. 7.1. Most all the thrust sheets have moved toward the 

 stable interior of the continent; only a few exceptions are known. One of 

 these is illustrated in section 2, Fig. 8.12. 



The Rome sheet was thrust forward at least 10 miles and then folded 

 into anticlines and synclines. See section 3, Fig. 8.12. Some of the folds 



