Metallogenic overview of the Nain Province, northern Labrador

CIM Bulletin, Vol. 89, No. 997, 1996

Derek H.C. Wilton, Department of Earth Sciences, Centre for Earth Resources Research, Memorial University of Newfoundland, St. John’s, Newfoundland

The Nain Province (NP) of northern Labrador is a >600 km long by =100 km wide Archean craton that has undergone relatively little mineral exploration until economically significant concentrations of orthomagmatic nickel sulphide were discovered by Diamond Fields Resources (DFR) at Voisey’s Bay. Due to the great time span between crust formation and final intrusive activity (ca. 3.9 Ga to 1.27 Ga), there were, however, numerous metallogenic events within the NP. The NP was intruded by the ca. 1.3 Ga to 1.2 Ga Nain Plutonic Suite (NPS) composite anorthosite-granite complex. The NPS divides the NP into the southern Hopedale Block (90 km by 150 km) and the northern Saglek Block (375 km long by =50 km wide). These two blocks appear to represent two distinct Archean cratonic nuclei, each with its own distinct metallogenic history. The NPS is a coalesced assemblage of composite intrusions which include anorthosite, troctolite, norite, gabbro and granite.

Mots Clés: Exploration, Metallogeny, Nain Province, Labrador, Hopedale Block, Saglek Block, Voisey’s Bay