Metallogeny of the Avalon Terrane During the Late Neoproterozoic

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This research program is focused on multiple, regionally extensive, metallogenetic episodes in the Neoproterozoic Avalon Terrane in Newfoundland (NL), and closely equivalent terranes in Nova Scotia (Mira Terrane) and New Brunswick (Caledonia Terrane). To date we recognize at least three distinct episodes of granitoid plutonism within the Avalon Terrane of NL (ca. 620 Ma, 585-575 Ma and 565 Ma) that show potential as fertile episodes for intrusion-related mineral deposits. These are under-examined, and under-explored, in terms of their potential for economic mineral resources. The program will provide detailed characterization of the features of both shallow epithermal Au-Ag and related porphyry-Cu(-Au) deposits within this terrane, incorporating determinations of the timing, depositional environment, and tectonic affinity of both the host volcano-sedimentary rocks and the parent plutons. This knowledge will be used to inform models for evolution of the Avalon Terrane in Atlantic Canada.******The scientific and technical approach will include:***- Petrographic, lithogeochemical and radiogenic isotope analysis (εNd) of host rocks, with particular relevance to establishing the exact style of arc volcanism that was contemporaneous with episodes of ore formation.***- U-Pb geochronology of parent granitoids and affiliated volcanic rocks, and Re-Os geochronology of molybdenite mineralization, to determine explicit timing of ore-forming events.***It will emphasize development and application of advanced microanalytical technologies, in particular,***- Sulfur isotope microanalysis, specifically to discern pyrite genetically associated with epithermal ore mineralization from that biogenically precipitated in sediments in near-surface (or shallow subsurface) intra-caldera waters contemporaneous with ore deposition.***- Integrated macro- (Visible/Infrared Reflectance Spectroscopy (VIRS)) and micro-scale analysis of phyllosilicate minerals to model alteration styles and zoning at the deposit scale. This will include advancement of Raman Spectroscopy, including micro- to nano-scale Tip Enhanced Raman Spectroscopy (TERS), for the study of alteration minerals in ore deposits. TERS has exciting potential to characterize extremely small volumes of alteration intimately associated with precious metal mineralization, enabling a deeper understanding of the mechanisms of Au-Ag precipitation in these systems.******The research program is designed to provide HQP (Highly Qualified Personnel) training and geoscience that drives innovation in mineral exploration. The knowledge developed in this study is directly transferable to the effective exploration, development and mining of mineral deposits in the Avalon Terrane. A longer term goal is to enhance understanding of the subaerial paleo-environment during the emergence of the first metazoan fauna in the Ediacaran period (635-541Ma). **