U. S. GEOLOGICAL SURVEY. 



St(«i;S'ffiL^«biEL.Lr.n:t VwVo 



TvIeHsFork Gw MS Tyler' s Fork 



1000 feet 



KEWEENAW SERIES. 



XCW Exposures of eruptives 

 South limit 



Upper Slate Member. 



Iron-bearintf Member 



fJMWS Mica-slate exposures ^ )»« Exposures of ferruginous schist. 



■iMkV B! SI Black slate exposures Limits of surface distribution 



iW(Q Quartzite exposures 

 ■*4<Gw. GraywacKe exposures 



PENOK 



Quartz- 



SI.Exposi. 

 Q Exposui 

 South 111 



^Exposures showing strike and dip. W Exposures showing no structure. ^ 



Scale of Map I inch=lmjle. ' 



DETAILED GEOLOGY OF THEi 



