19 20 



MtDDlE «NU 



UPPEH 

 OROOVICUN 



crdovm:ian 



'•ALE020IC METAMORPHIC KEWEENAWAN BELT SERIES LATE T UPPER MIDDLE AND HA 



PALEOZOIC PRE CAMBRIAN HURON IAN LOWER HURON tAN 



STINGS AND EARLIER ' KEEWATIN 



RENVILLE PRE CAMBRIAN 



Ek3 OS 



:-CAMBR 

 FFERENT 



18 



LAURENTIAN ' LAURENTIAN" PRECAMBRIAN GNEISSES AND TERTIARV POST-CAMBRIAN PRE CAMBRIAN 



UNDIFFERENTIATED SCHISTS EFFUSIVES IHTRUSIVES 1NTRUSIVES 



