| Bagenheigeqier lead-zinc polymetallic deposit lays in the Xing'an District, in the province of inner Mongolia, which is polymetallic deposit with lead and zinc mostly, iron and copper and so on. During the field work, ivernite keeps touch with the marble, and between both skarn happens with the ore. In the deposit, sphalerite, pyrite, galena can be seen, at the same time, gangue minerals conclude calcite, garnet, fluorite, quartz, chlorite and so on. So the conclusion that one forming type of the deposit is skarn deposit.With the help of the optical rock features, there are totally four groups of rocks in the deposit, including J3mk,J3mn, J3b and P1d. Granite porphyry and ivernite also outcrops in the district, which have the relationship with the deposit ore.During the temperature of fluid inclusion in the quartz and carbonate, the limit of the homogenization temperatures of quartz and carbonate are 190°~270°and 170°~230°, mostly 210°~250°and 190°~230°, and the average is 243.66°and 206°. During the field job, quartz forms latter than the ore, and carbonate is close to it, so, to some extent, the temperature indicates that this deposit formed in the moderate temperature condition. At the same time, according to theδ18O-δD diagram, quartz and carbonate are the results of the atmospheric precipitation and magmatic water, and from another diagram, the forming sequence can be judged that is quartz, fine-grain carbonate and coarse carbonate by the time.According to the sulfur-lead isotopic elements data, such conclusions can be drawn:①Sulfur element comes from mantle, when regional structural surrounding is compressing at Jurassic Period. Plenty of volcanic rocks form, while magmatic thermal which contains mantle and low-and-up crust matter upwell, and the matters precipitate in the altered andesite; magmatic rocks which contain Pb2+,Zn2+and other ions upwell along the N-E fracture, and then mix with the S2- in the altered andesite, so the metallic sulfide precipitate.②From the lead isotopic elements data, it's the conclusion that the sulfides in the deposit district are coming from the orogenic belt, which is accorded with the fact that this regional structural background. The mineralizing fluid hosting the lead ion are supposed to get from the granite porphyry and ivernite in the deposit district, which comes from lower-middle crust and are influenced by the mantle.Long-time magmatic hydrothermal fluid containing so much mineralizing matter concentrating in the magmatic clastic rock and tuff, and latter hydrothermal fluid got the mineralizing matter, and then the metallic sulfide formed. According to the output, the style of the filling up, composition of the ore, and so on, the style of the deposit is skarn deposit and moderate hydrothermal alteration deposit,.Yanshan late period granite porphyry, ivernite and other intrusive rock intrude the ore-hosting rock, and the formation of the ore has close connection with the magmatic rocks. Analysis gets it that ord-forming period is Yanshan late period. The factor that controls the deposit is fault and rock mass.
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