156 Bulletin of Laboratories of Denison University [Voi. xn 



Except the Knox dolomite, all the formations shown on 

 the map to the west of the Cartersville fault belong to the middle 

 and lower Cambrian. The Knox dolomite is here included en- 

 tirely in the Silurian, although strong reasons appear for group- 

 ing the lower portion of this formation with the Cambrian. In 

 Figs. 2, and 9, the Knox dolomite is designated as partly Cam- 

 brian and partly Silurian. 



The Paleozoic Rocks of the Cartersville Disttict on the West Side 



of the Fault. 



The Weisner Quartzite. — The Weisner quartzite is in con- 

 tact on the east side with the Cartersville fault. The principal 

 area of the quartzite occupies the middle portion of the map as 

 an irregular strip, having an approximate north-south extension 

 of about I 5 miles and, in width, varying from i to 3 miles. It 

 is composed principally of a fine-grained quartzite, with addi- 

 tional bands of a fine-grained conglomerate and micaceous 

 shales. Wherever exposed, the formation shows evidence of 

 intense folding, fracturing and crushing. The absence of satis- 

 factory exposures, added to the complex folding of the beds, 

 prevents an accurate estimate of its total thickness, but it is 

 probably not less than 2000 to 3000 ft. thick in this locality, 

 as stated by Hayes. 



Hand-specimens of the Weisner quartzite, carefully col- 



« 



lected by the writer from the numerous outcrops of the entire 

 area exposed in Georgia were thoroughly mixed and prepared 

 as one sample, a representative part of which yielded, at the 

 Pratt laboratory, Atlanta, the results shown below. 



Analysis of Weisnet Quartzite, Cartersville District. 



SiOj, ......... 90.36 



TiO,, ......... 0.07 



AljOj, 1.52 



FePs. 0-57 



CaO, ......... 0.27 



MgO, ......... 0.27 



MnO, ......... None 



NejO, -...-.... 0.43 



KjO, ......... 0.16 



