Precambrian crustal growth in the Canadian shield: investigating a billion year of tectono-magmatic evolution in the Winnipeg River subprovince, Ontario, Canada

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Plate tectonics (i.e., plate movement and interaction) occurred throughout all Earth's history, but driving forces and associated processes evolved during the Archean and Proterozoic eons, and resulted in global tectonic, magmatic, and environmental changes. Ultimately, these changes have implications on the nature, abundance and spatial distribution of base (e.g., Ni, Cu, Zn), precious (e.g., Au) and strategic (e.g., Li-REE-Nb-Ta) metal deposits in Precambrian shields. Each continental crust fragment of Precambrian age represents a piece of the puzzle, however their integration in a unified, global-scale, plate tectonics evolutionary model is challenging. The long term objective of this research program is to use multi-disciplinary approaches to propose a comprehensive geodynamic interpretation of the Canadian shield, and test it against other well documented Precambrian cratons in South Africa, Australia, West Africa and South America. The Canadian shield is an ideal study area that includes some of the largest Archean crustal fragments (e.g., Superior Province) that are bounded by extensive Paleoproterozoic orogenic belts (e.g., Trans-Hudson), and displays a nearly continuous crustal growth and recycling spanning half of the Earth's history (i.e., from 4.0 Ga to 1.8 Ga). In this program, the emphasis will be on the structural, metamorphic and geochemical evolution of the Precambrian continental crust, and its implications to prospect for natural resources. In the next five years, the short term objective is to unravel a billion year of Archean crustal history in the Winnipeg River subprovince, between Sioux Lookout and Kenora, north-western Ontario. The variety of ages, rocks types, structural patterns and metamorphic grades in the Winnipeg River subprovince makes it an appropriate study area to decipher the broader geodynamic evolution of the western Superior Province. This research program will: (1) develop a new understanding of crustal growth and recycling in the Winnipeg River subprovince, using structural, geochronological, lithogeochemical, and metamorphic constraints; (2) recognize possible secular geodynamic changes between the Paleo- Meso- and Neoarchean evolution of the Winnipeg River subprovince; (3) propose a revised tectono-stratigraphic model of the western Superior Province, and test its implications for Archean geodynamic processes, which will be a first step toward the long term objective of this research program; (4) deliver a comprehensive and multi-disciplinary study of a gneiss-granitoid "pinkstone" belt in the Superior Province, with integrated investigations on the origin and distribution of strategic metal occurrences, which may assist future exploration projects and ultimately enhance the mineral resources potential of north-western Ontario.