Voisey?s Bay ? Geology, Geochemistry and Genesis

Abstract

The ~ 1333 Ma Voisey's Bay Intrusion represents one of the earliest magmatic events recorded in the development of the Nain Plutonic Suite. The intrusion was likely emplaced at a depth of ~14 km. Sulphide saturation occurred due to the assimilation of bulk Churchill gneiss in a series of sub-chambers below the current level of erosion. The current economic ore zones formed by the accumulation of magmatic sulphides in physical traps from a pulsed series of sulphide-laden magmas derived from the sub-chambers. The initial melt had an MgO content of >8 wt % and a geochemical and isotopic composition similar to some Proterozoic flood basalts.