"Metallogeny of arcs, from subduction-related to post-subduction processes"

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Magmatic arcs related to the subduction of oceanic lithosphere are prospective for porphyry Cu±Mo±Au and epithermal Au deposits. Recently, porphyry and epithermal deposits that formed after subduction ceased have also been recognized in several parts of the world; these deposits may be generated during or after collisional processes. This research program aims to examine the tectonic and magmatic controls on porphyry and epithermal ore deposit formation that operate both during and after subduction. The main questions to be addressed by this research program are: (1) How do magmas with ore-forming potential ("fertile" magmas) form in arc environments?; (2) Can any chemical or mineralogical indicators of magma fertility be identified?; (3) Can we learn anything about fertile magma formation by studying the exposed deep crustal roots of arc systems?; and (4) What does the occurrence of post-subduction porphyry and epithermal systems tell us about the way subduction processes affect the deep lithosphere? These questions will be addressed by targeted fieldwork, with special focus on the arc terranes of North and South America, and the Tethyan belt of Turkey-Iran-Pakistan-Tibet. Geochemical, isotopic, and geochronological analyses will be undertaken on collected samples to constrain the timing and evolution of fertile magmatic suites within their regional tectonomagmatic context, and to identify key parameters that control prospectivity. High pressure/temperature experimental work will also be undertaken to explore the behaviour of metals during melting of subduction-modified lithosphere. This research is expected to be of interest to the Canadian and international mineral exploration industries, and will also shed light on magmatic processes occurring in the deep lithosphere during and after subduction.