Abstract:Served as one of three giant metallogenic domains, a lot of world-class ore-forming belts (deposits) occurred in Tethyan metallogenic domain, such as Pontides, Sahand-Bazman, Chagai, Yulong and Gangdese. In order to further understand the genesis and mineralization of Miocene porphyry copper deposits in Tethyan domain, the geolgocial, geochemical and Sr-Nd-Pd isotopic data of ore-bearing porphyries from typical porphyry Cu deposits in Sahand-Bazman, Chagai and Gangdese belts have been compared and analyzed, and their petrogenesis, source and tectonic environment have been discussed, and their tectonic evolution and metallogenic process have been concluded and summarized in this paper. The geochemical resutls suggest that the Miocene porphyries in these three belts show the characteristics of calc-alkaline I-type granite, with adakite magmatic affinity. Compared with the lithogeochemical features of porphyries in the Gangdese belt, the ones in Sahand-Bazman and Chagai belts show the transitioning characteristics of from arc magmatic suites to adakites, which might be caused by the partial melting of MORB-derived amphibole eclogite or eclogite occurred in the magma source with a greater degree. The Sr-Nd-Pd isotopic data suggests that these ore-bearing porphyries might be sourced from the mixture of crust and mantle controlled by magma, showing DUPAL anomaly. After comprehensively analyzing the geological, geochemical and istopic characteristics of these porphyry deposits, it’s believed that these ore-bearing porphyries were formed in the island arc setting of collision-orogenic belt, serving as the partial melting products of thickened lower crust during the subduction of oceanic crust and the continental collision.