U. S. GEOLOGICAL SURVEY. 



KEWEENAW SERIES. 



'jSSSflA Exposures of eruptives. 



^= S Sandstone 

 South limrt. 



Upper Slate Member. 



fGw GraywacKe exposures 



SS Exposures of ferruginous schist. 

 ■ Limits of surface distribution 



PEN 01 



Iron-bearind Member Quartz 



SI.Expoi. 

 Q. Expos" 

 South 



= Exposures showing strike and dip. 'iW Exposures showing no structure. 



Scale of Map I inch=lniile. 



DETAILED GEOLOGY OF THEl 



