272 



THE VERMILION IRON-BEARING DISTRICT. 



in whicli no rocks are exposed or in wliicli lliere is only an occasional iso 

 lated exposure of rotten schistose rock. In sncli exposures the characters 



ALGONKIAN 



LOWER h j URONIAN 



Ogishke conglomerate 



ARCHEAN 



Granite Granite porphyry 



(with observed (.without observed 



strike and dip) strike and dip) 



Scale 

 O Va- 



FiG. 17.— Detail geologic map showing exposures in a small area on West Gull Lake. 



