| Badi orefield is located in Shangjiang county of Yunnan province,outcrops between the Zhongza-Shangri-La piots in Yunnan Sanjiang. Be located between the Qiuduo-Ludian trunk fracture (Jinsha River fracture) and Zhongdian trunk fracture. The predecessors have done some basic geological and geological prospecting work and achieved-given geological knowledge, but for the mine ore types, the mineralization period, the source of ore-forming fluid, the genesis of the deposit and other aspects of the blank. The macroscopic geological phenomenon and microscopic geological phenomenon combination is weak, the metallogenic regularity is lacking. Therefore, this article by Bardi copper detailed geological survey, profile, drilling and trenching catalog, combined with modern analysis and testing means, comprehensive study of geological background, geological characteristics, ore fluid geochemistry, isotope geochemistry and other aspects of the mining area, obtained the following understanding:(1) The main ore-bearingrock is low greenschist facies rocks of Judian group metamorphic rocks of the Neoproterozoic.(2) Containing the gas-liquid inclusions, containing CO2inclusions and halite bearing inclusions are developed in quartz veins. Sub minerals are mainly pyrite. Fluid inclusion microthermometric and Raman spectroscopy studies found that, there are3different nature of the ore-forming process:low temperature, low salinity in H2O-NaCl fluid; Medium temperature, low salinity in CO2-H2O-NaCl fluid; High temperature, Fe rich, high sulphur of fluid. Mineralization fluid with medium temperature (244.7～296.3)℃, low salinity (0.71%～11.89%NaCl), high density (0.9573～1.0523) g/cm3as the characteristic, rich in CO2, in which the carbon density of (0.5753～0.7576) g/cm3. The coexistence of gas-liquid inclusions degree and CO2bearing three-phase inclusions in the space of different gas filling, also has the homogenization temperature close, and all manner of different display characteristics, boiling of fluid inclusion assemblages. Boiling temperature, pressure changes may be main mechanism of ore-forming elements in precipitation.(3) The test results of sulfur isotope δ34S=13.29～15.52‰, the range is2.23, the average was14.32‰, the sulfur source may come from the host rock, influenced by seawater sulfur(4)8D ranges from-107‰～-87‰,δ18O values at4.96‰～5.86‰in fluid inclusions. Metallogenic fluid mainly falls under the magmatic water and metamorphic water, at the critical line of atmospheric precipitation and hydrothermal exchange inside, away from the rain water area, so the judge metamorphism the water has an important relationship with the hydrothermal ore deposits, and atmospheric precipitation may be late mixed.(5) The Bardi copper deposit is mainly affected by regional metamorphism reworking of the Indosinian movement dominated by tectonic, metamorphic hydrothermal deposit ore controlling tectonic effect. |
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