154 Bulletin of Laboratories of Denison University. [Voi xii 



thereabouts. In length they vary from 3 to 8 miles, and they 

 cut the strata at close intervals into narrow strips, forming 

 monoclinals, which dip steeply toward the east. Tiie faults of 

 this type in the region already mentioned result in l<Mig and 

 narrow strips of the underlying Conasauga shales, which form 

 the narrow valleys penetrating southward into the Knox dolo- 

 mite plateau. 



For the reason that the two types of faults here distin- 

 guished are seldom found intersecting each other, the faulting 

 is inferred to belong to different and, therefore, distinct periods 

 of disturbance. 



The Cartersville District. 



One of the principal manganese-producing districts in 

 the Southern Appalachians is in the vicinity of Cartersville, 

 Bartow county, Georgia, about 50 miles northwest of Atlanta. 

 Manganese-mining in this district dates back as early as the 

 year 1866, when 550 tons of the ore are reported to have been 

 mined.' From that time to the present the Cartersville district 

 has been one of the three principal producers of manganese in 

 the United States. Excepting the Cave Spring district, the 

 entire production of manganese in Georgia has been from this 

 district. 



The older crystalline and metamorphic rocks occupy the 

 east half of the area shown on the map (Fig. 3). The Paleozoic 

 formations of the valley province occupy the west half of the 

 mapped area. The line separating the two groups is an irregu- 

 lar one, marking the position ot the Cartersville fault. 



The succession of formations in ascending order, on the 

 west side of the Cartersville fault, is as follows : 



Silurian . . Knox dolomite. Cheity magnesian limestone. 



C Conasauga shale. Olive clay shale, chiefly. 



I Rome shale and sandstone. Purple, white, green and brown 



r- \ ■ I Sandstone, and interbedded sandy shale. 



Cambrian, \ ' _ ■' 



I Beaver limestone. Blue siliceous limestone. 



1 VVeisner quartzite. Quartzite, coarse conglomerate and niica- 



L ceuus shale. 



' Mineral Resources of the United States, 1S85, p. 329. 



