The Yangla copper deposit, situated in the middle section of Jinshajiang tectonic belt between ZhongzaZhongdian plate and ChangduSimao plate, is a representative and giant copper deposit that has been discovered in JinshajiangLancangjiangNujiang region in recent years. Metalliferous minerals consist of chalcopyrite, pyrite, pyrrhotite, galena, bismuth, bismuthinite, arsenopyrite, cobaltite and molybdenite. Based on the mineral association, the paper infers that the deposit is a medium to high temperature hydrothermal deposit. There is a coupled relationship between Yangla granodiorite and copper mineralization in the Yangla copper deposit. A comparison of the REE and trace element compositions of the copper ores with those of the Yangla granodiorite, and S, Pb isotopic composition of the Yangla copper deposit indicate that the oreforming fluids are derived mainly from the mantle, with minor contributions from the magma. In the late Early Permian, the Jinshajiang oceanic plate was subducted to the west, resulting in the formation of a series of gently dipping thrust faults in the Jinshajiang tectonic belt，meanwhile, accompanied magmatic activities. In the early Late Triassic, which was a time of transition from collisionrelated compression to extension in the Jinshajiang tectonic belt, the thrust faults were tensional, it would have been a favorable environment for oreforming fluids. The ascending magma provided a channel for the oreforming fluid from the mantle wedge. After the magma arrived at the base of the earlystage Yangla granodiorite, the platy nature of the granodiorite body would have shielded the latestage magma from the fluid. The magma cooled slowly, and some of the oreforming fluid in the magma moved along a gently dipping thrust faults near the Yangla granodiorite, resulting in mineralization.
