Art IX] Watson, Manganese Oj'e Deposits of Georgia. 163 



lite) schist. According to Hayes.' both diabases and diorites 

 are represented in the area. Diorite is regarded as the com- 

 monest type of rock, and it is now mostly altered into the am- 

 phibolite schist. 



Stmetiiral I'eatiwes. 



It is only necessary in this paper briefly to call attention to 

 the broader structural fealures ol the district, since the manga- 

 nese deposits are limited to the residual clays of several of the 

 formations, and only in a very general way do they show any 

 rdaiioiis to tlie structure In his paper on the iron ore-deposits 

 of the district. Haves has discussed in some detail and in a 

 m 'St t xcellent manner the structure ot the region, to which pa- 

 per the reader is reierred for further details.^ 



The aiea has been one of intense and prolonged disturb- 

 ance (compressive forces) operating in a northwest-southeast 

 direction, resulting in profound alteration of the rocks, — their 

 fcjlding, crushing and fracturing. In places, some of the rocks, 

 originally unlike, are so profoundly altered that they are with 

 great difficulty distinguishable at present. On the east side 

 of the fault-line the rocks are mashed and squeezed, and the 

 slaty and schistose stiucturts strongly developed, while on the 

 west Side the rocks are complexly folded and fractured. In 

 addition to the folding, the Weisner quartzite especially has 

 bten much crushed and in places brecciated, probably indi- 

 cating faulting. Some of the more massive formations, such as 

 the Knox dolomite, resisted the folding to a greater degree 

 than others. 



The overthrust fauit which separates the older crystalline 

 rocks from the P.ileozoic sediments is tlie principal structural 

 fea'iureol the region Its position is shown on the accompany- 

 ing map (Fig. 3), where it is observed to pass some distance to 

 the east and south of CartersviUe, from which town it derives 

 its name. Its line ot contact is here marked by the rocks of 

 the Ocoee series on the east side, brought next to the rocks of 

 the Cambrian on the west side. 



' ihui., p. 40S. ^ op. ctt., pp. 403-419. 



