Gold in eskers and gyttja overlying auriferous till, Regnault deposit, Quebec

Abstract

The Regnault gold deposit in Quebec, Canada, was discovered by Kenorland Minerals North America Ltd in 2020 following identification of a gold-in-till dispersal train. In 2022, two non-traditional media – eskers and organic lake-bottom mud (gyttja) – were sampled to determine if they likewise contained gold anomalies that vectored the mineral deposit. Striking, coherent (mappable) anomalies exist in both media. The gold-in-esker dispersal train has a similar pathfinder element association as the gold-in-till dispersal train (e.g. Te, W) but contains approximately twice the gold (average 73 ppb Au) in the <63 µm fraction. It is hypothesized to be a meltwater-sorted version of the gold-in-till train, sourced from the erosional esker corridor some 3 km upflow. By contrast, the gold-in-gyttja dispersal train is substantially different to both the gold-in-esker and gold-in-till dispersal trains. It has lost significant association with pathfinder elements, contains an order of magnitude less gold (average 4.2 ppb Au), and is tentatively hypothesized to have a hydromorphic origin, sourced primarily from the gold-in-till dispersal train. The main takeaway from the study is that the sampling of any of these three media – eskers, gyttja or till – could have conceivably led to the discovery.