Recognizing IOCG alteration facies at granulite facies in the Bondy Gneiss Complex of the Grenville Province

Olivier Blein (1) , Louise Corriveau (2)

1 BRGM - Bureau de Recherches Géologiques et Minières (BRGM)
2 NRCan - Natural Resources Canada

The Bondy gneiss complex in the southwestern Grenville Province of Canada, hosts a series of granulite facies 1.4–1.35 Ga mafic to felsic volcanic rocks. Metamorphosed hydrothermal alteration zones constitute large sectors of the complex and have mineral occurrences. Mineral assemblages and lithogeochemical analysis of meta-hydrothermal zones have attributes of Na, CaFe , K-Fe, K, Mg, argillic, phyllic and advanced argillic altered volcanic rocks. In alteration discrimination diagrams, the hydrothermal system shares attributes of IOA-IOCG systems that evolve toward epithermal caps (e.g., Great Bear magmatic zone, Canada; Central Andes, Chile). The Bondy footprint is significantly distinct from VMS deposits and other deposit types. We thus interpret the Bondy hydrothermal system as prospective for the variety of mineralisation types typical of Proterozoic IOA-IOCG-epithermal systems.

Keywords: granulite; IOCG; metamorphosed alteration zones; Grenville

Domains: Applied geology; Geochemistry

Olivier Blein, Louise Corriveau. Recognizing IOCG alteration facies at granulite facies in the Bondy Gneiss Complex of the Grenville Province. SGA Québec 2017, Aug 2017, Québec, Canada. ⟨hal-01488295⟩