Geochemistry and genesis of a mafic-ultramafic hosted VMS occurrence. Marathon, Ontario

Geochemistry and genesis of a mafic-ultramafic hosted VMS occurrence, Marathon, Ontario 

Marc L. Rinne Peter N. Hollings Aubrey J. Eveleigh  

Keywords voicanogenic massive sulphide, Superior Province, ultramafic, exploration geochemistry, Schreiber-Hemio greenstone belt 

The Big Lake Cu-Zn-Ag-Au voicanogenic massive sulphide (VMS) occurrence is hosted in mafic-ultramafic strata of the Schreiber-Hemio greenstone belt near Marathon, Ontario (Fig. 1). This VMS is unusual in that it is one of a few documented VMS occurrences in sequences lacking felsic volcanic or volcaniclastic rock. 

The Wawa subprovince is a volcano-plutonic assemblage of 2.88-2.72 Ga rocks (Percival et al. 2006) accreted to the southern part of the Superior Province during the end of the Kenoran Orogeny, ca. 2.69 Ga. Extending approximately 1000 km from NE Minnesota to just south of James Bay, the Superior Province is 

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