An International Collaborative Investigation of Khoy Ophiolite, NW, Iran

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9903249GhaziThe ophiolites of the Bitlis-Zagros Suture Zone zone form a discontinuous linear belt of Tethyan oceanic fragments which form a bridge between the Samail Ophiolite in Oman and the Troodos ophiolite in Cyprus. The Iranian ophiolites of the Bitlis-Zagros Suture Zone include complexes at Neyriz, Kermanshah and possibly at Khoy. Currently there is an immense gap in our knowledge about many fundamental aspects of genesis of these ophiolites (e.g., the mantle sources, the petrogenetic origin, the tectonic environment and timing of formation, timing and mechanism of emplacement) and thus in our understanding of the Mesozoic-Cenozoic geology of the Middle East and Eastern Mediterranean regions as well as of Tethyan paleogeography. The Khoy ophiolite of northwestern Iran is especially suitable to study because; 1) it is one of the largest intact complexes in the region with a mappable ophiolite pseudostratigraphy, 2) it has a well-defined metamorphic sole whose rocks show effects of an inverse thermal gradient from amphibolite facies to greenschist facies, 3) it is located at an important junction between the belts of Mediterranean and Middle Eastern ophiolites along the Arabian promontory, and 4) it has been overlooked in tectonic models for reconstruction of closure of the Tethys Ocean. The results of this study will advance understanding of the physiochemical processes involved in magmatism at oceanic spreading centers, formation of oceanic crust, and ophiolite genesis and emplacement. Ultimately, we hope to generate a modern, high-quality geochemical database and evaluate ancient tectonomagmatic processes in this little-studied region and answer some of the fundamental questions about Tethyan and Indian Ocean magmatism, timing and tectonics of ocean closure and the evolution of geochemical domains within the upper mantle, and ophiolite genesis in general.