引用本文：吕鹏瑞,姚文光,张辉善,张海迪,洪俊,刘生荣.2020.特提斯成矿域中新世斑岩铜矿岩石成因、源区、构造演化及其成矿作用过程[J].地质学报,94(8):2291-2310. Lü Pengrui,YAO Wenguang,ZHANG Huishan,ZHANG Haidi,HONG Jun,LIU Shengrong.2020.Petrogenesis, source, tectonic evolution and mineralization process of the Miocene porphyry Cu deposits in the Tethyan metallogenic domain[J].Acta Geologica Sinica,94(8):2291-2310.
Abstract:Several world class ore- forming belts (deposits) such as the Pontides, the Sahand- Bazman, the Chagai, the Yulong and the Gangdeseoccur in the Tethyanmetallogenic domain, referred to as one of the three giant metallogenic domains. In order to further understand the genesis and mineralization of Miocene porphyry copper deposits in the Tethyan domain, the geological, geochemical and Sr- Nd- Pb isotopic data of ore- bearing porphyries from typical porphyry Cu deposits in the Sahand- Bazman, the Chagai and the Gangdese belts have been analyzed and compared, their petrogenesis, source and tectonic environment have been discussed, and their tectonic evolution and metallogenic process have been deduced and summarized in this paper. The geochemical results 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 the Sahand- Bazman and the Chagai belts show the transitioning characteristics 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- Pb isotopic data suggests that these ore- bearing porphyries might have been sourced from a mixture of crust and mantle controlled by magma, showing DUPAL anomaly. After comprehensively analyzing the geological, geochemical and isotopic characteristics of these porphyry deposits, it is 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.