Lithogeochemical Vectors for Hydrothermal Processes in the Strange Lake Peralkaline Granitic REE-Zr-Nb Deposit

Extreme enrichment and postmagmatic hydrothermal mobilization of the rare earth elements (REE), Zr, and Nb have been reported for a number of anorogenic peralkaline intrusions, including the world-class REE-Zr-Nb deposit at Strange Lake, Quebec, Canada. Establishing lithogeochemical vectors for these types of deposits is a challenging task because the effects of hydrothermal processes on element distribution are poorly known and the relationships of alteration types to mineralization stages have not been well documented. Here, we present results of a detailed mineralogical and geochemical investigation involving a dataset of over 500 mineral and bulk-rock analyses of a northeast-southwest section through the potential ore zone at Strange Lake. Based on these data, we develop a model that explains the role of hydrothermal processes in concentrating metals in peralkaline granitic systems and identify lithogeochemical vectors for their exploration.[...