The geology of the Windfall gold deposit, Québec, Canada

Abstract

The Windfall deposit is an advanced-stage exploration gold project owned and operated by Osisko Mining Inc. and is located in the northeastern portion of the Abitibi greenstone belt, Québec, Canada. This is the first deposit-scale study and as such aims to provide an understanding of its geological setting and the evolution with a focus on the origin of gold mineralization. The study integrates several aspects, including: 1) geological mapping; 2) characterization of the various host rock lithologies and their alteration; 3) results of new age dating; and 4) characterization of the different vein types, their mineralogy and chemical and textural nature of the gold mineralization. The overall conclusion of the study suggests that the gold deposit formed ca. 2.7 Ga due to a magmatic-hydrothermal fluid exsolved from an underlying magma now represented by a swarm of felsic dike rocks spatially associated with the ore body.