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Abstract
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Subduction zones are the world principal tectonic setting for exploration and exploitation of copper and gold as well as an important target for molybdenum, silver, lead and zinc. Due to their major economic interest, various conceptual models were proposed that emphasize the interactions between subduction dynamics and ore genesis. However, most of these models are described in two dimensions (2D), thus underestimating the importance of along-strike changes of slab dynamics such as slab break-off or tearing that strongly affect the upper plate deformation regime as well as the distribution and composition of magmatic products in the overriding plate. In order to provide new regional guidelines for mineral exploration, metallogenic models have to consider these geodynamic processes, requiring studies of the space and time evolution of ore deposits within a 3D tectonic framework; such frameworks being rarely available. The Mediterranean subduction zone belonging to the Tethyan orogenic belt (Figure caption) is well suited for this purpose with (1) a variety of ore deposits formed from late Cretaceous to Neogene times and (2) a complex tectonic evolution that includes oceanic and continental subduction, orogenic building, back-arc opening, slab rollback and tearing, and asthenospheric upwelling. To study the influence of evolving subduction dynamics on ore-forming mechanisms along the Mediterranean subduction zone, we examined the space/time evolution of metal occurrences by integrating a compilation of metallogenic data to a recently developed kinematic reconstruction model of this region. Resulting paleotectonic maps indicate an Eocene Cu-rich period followed by a late Eocene-Miocene Pb-Zn- then Au-rich period. In light of additional geochemical and physical constraints on the 3D tectonic and magmatic evolution in this region, we discuss in this paper the role of subduction-related processes, such as arc magmatism, slab retreat and tearing, back-arc extension and as
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