Art. IX.] Watson, Manganese Ore-Deposits of Georgia. i 5 i 



Traces of at least three rather distinct base-leveled plains 

 appear in the region. According to Hayes' the highe.-^t and 

 earliest one of these plains was probably formed during Cretace- 

 ous time, and the period of rest during which the atmospheric 

 forces were operative is believed to have been much longer than 

 th.it of the formative period of either one of the subsequent 

 plains. The present streams were revived by the recent uplift, 

 and tliey are now engaged in sinking their channels in the sur- 

 face of the last base-level. 



Fig. I. 



te.4^lF^^'^Ti^^P^^''^ 



Sketch-Map of a Part of Georgia, Showing the Distriiiution of the Manganese" 

 Deposits (Represented by the Black Area.s). 



Stratigraphy. — The rocks of the region range in age from 

 lower Cambrian to Carboniferous, and they include slates, lime- 

 stones, shales, sandstones and conglomerates. No igneous 



^ Sixteenth Annual Report U. S. Geo!. Surrey, 1S95, ^'^'^^ III., pp. 553-554- 



