Mapping the Archean mantle through the geochemistry of TTG and lamprophyres

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This study will investigate the field, geochemical and isotopic characteristics of 2.7 Ga tonalite-trondjhemite-granodiorite (TTG) suites and their major and accessory mineral phases, in several areas of the Superior Province that differ in terms of the thickness of their cratonic roots and histories of upper crustal development. This study of mainly mid- and upper-crustal processes will be linked to contemporaneous events in the lower crust and mantle via a study of crustal and mantle xenoliths in spatially associated late Archean lamprophyres. This will allow us to clarify the formation and stabilization of the world's largest craton, and also provide important insights into the ongoing controversy of granite magma genesis and emplacement processes. In addition combining geochemical and isotopic studies of TTG and lamprophyre hosted xenoliths in well-mapped and geochronologically well-constrained greenstone belts, will allow us to evaluate the nature of Archean tectonic processes and compare them with those of the Phanerozoic. By illustrating the nature of Archean subduction processes and variations in the nature of subcontinental lithospheric mantle, as well as demonstrating correlations between xenolith-overprinting fluids and gold-bearing solutions, this study will make a significant contribution to the debate about the scale and architecture of orogenic gold systems.