Study Of Geological Characteristics Of Copper Nickel Ore Deposit Of Funing Weidong Yunnan

Yunnan Funing County copper nickel ore mining area is located in the transition zone between Yangtze paraplatform and south China Caledonian fold belt. It is in the south section of the secondary structural unit in Gejiu and the right of basin-and-range province, and in the southeast of the third structural unit of Guangnan and Funing rift trough.This copper and nickel mine is about0.97square kilometers and is under the jurisdiction of Xinhua Town Funing County. The main exposure strata of this area are Permian. The Norite Gabbro intrusion covered the area well in indosinian. The rock body is in an irregular shape. It intrusions fracture or fold which is consisted by Wujiaping Formation of the upper series of Permian System (P2W) and Middle Triassic reservoirs Baipeng Group. The ore-bearing lithofacies of main mining area is olivine norite gabbro and containing olive norite gabbro.The three main ore types are sparse disseminated ore which is spotted structure or sideronitic texture in local, sparse-dense disseminated structure and vein type ore.Influenced by the Dongbao-nasanxu fault zone, the structure of the mine is divided into before and after invasion of fracture rock intrusion. Ore body is mainly produced in NNW (north northwest) direction, southwest dip.This article starts with the geologic feature of the ore deposits, based on previous researchers’ results, and combines with the identification of thin sections and electron probing analysis, the regional ore-forming geological background, geologic feature of ore-bearing rock and ore deposit of Funing County copper nickel ore mining has been compared with the typical copper-nickel deposits in our country. With the help of a project team’s analysis of element geochemistry, we have learned those:1. The distribution of rock and ore body are controlled by structure, and ore body has a large output scale, in the fracture.2. Ore body lies in diabase, gabbronorite and olivine gabbro norite, and mostly in olivine gabbro norite, and it usually has a large output scale.3. According to the electron probing analysis, metallic mineral mainly lies in forsterite which has a small number of labradorite around. There is also forsterite along the edge of veinlet structured magnetite. The closer to the magnetite the lower magnesium content but the higher ferric content. According to this, it infers that magnesium migration and enrichment occurred.4. Combine with the studies of the occurrence feature of the deposit and their architectural features, and the electron probing analysis, we can divide the deposit formation into four different stages of mineralization, they are early magmatic liquation-crystallization differentiation stage, late magmatic mineralization stage, slurry injection mineralization stage and late ore-forming stage.5Compare Weidong deposit with the typical Cu Ni sulfide deposit in our country (Hongqiling area in Jilin province), there is only a big difference exist in the mineral composition. According to the major element analysis of the three ore rocks, we know that there are different lithofaces in the same rock mass. This explained that ore-bearing facies may destroy the original rule between the components of mantle-derived magma because of the addition of the crustal materials into the magna. And this additional material also plays an important role in promoting the liquation processes.6. Integrate the analysis of the field geological survey, identification of indoor thin sections, electron probing, and with the help of the comparation analysis with the typical Cu Ni sulfide deposit in China and the analysis of element geochemistry, it infers that ore deposit is formed by early magmatic liquation-crystallization differentiation and later hydrothermal superimposition.