Regional Metallotectonic Settings of Porphyry Deposits in Southwestern China
QIN Jianhua,DING Jun,LIU Caize and ZHANG Qiming(Chengdu Center,China Geological Survey,Chengdu 610081,Sichuan,China)
This paper has reviewed and discussed the regional metallotectonic settings of the porphyry Cu(-Mo-Au) deposits in southwestern China. The porphyry deposits in southwestern China are located tectonically in the east part of the global Tethyan porphyry metallogenic belt,which are associated with the evolution of the Tibet plateau,formed in the separate evolutional stages. Temporally,the porphyry deposits in southwestern China occurred in four stages:Late Triassic,early Cretaceous,Palaeogene and Miocene. The regional metallotectonic settings of porphyry deposits in southwestern China are diverse,spanning from island arc,syn-collisional to post-collisional and continental transform plate boundary settings. According to the petrogenic and mineralization ages and tectonic settings,five porphyry metallogenic belts are divided in southwestern China,which are,respectively,the Yidun-zhongdian Indosinian porphyry metallogenic belt,Yulong-Malasongduo Palaeogene belt,Lijiang-Jinping Palaeogene belt,Gangdese Palaeogene-Neogene belt,and Bangong-Nujiang Yanshanian porphyry metallogenic belt. Finally,like the most porphyry deposits in the world,the close spatial relationship to the regional strike-slip faults is evident for all five porphyry metallogenic belts in southwestern China,with the porphyry deposits tending to cluster around the strike-slip faulted zones.