| Weibao Pb-Zn ore deposit located in the border of Qinghai and Xinjiang, East Kunlun Qimantage, is found by Xinjiang Geophysical and Geochemical Institute in recent years, is one of the largest and most typical deposits. By taking Weibao Pb-Zn ore deposit as research object, offers beneficial reference to exploration and study work about the regional same kind of deposits.In this paper, the full collection on the basis of previous data, through field inves-tigation and comprehensive study of indoor work on the regional dimension Pb-Zn geological background, geology, mineralization related geochemical and other conducted a study on the ore-forming fluid source, the ore sources and structure environment, and summarizes the genetic model of the deposit.(1) Weibao ore deposit is a stratabound lead-zinc deposit, strictly controlled by lithology. Jxl formation is composed of banded epidote-diopside skarn, marble ceramics, marble of limestone, green clay sericite phyllite, sericite fiber amphibole schist, and the skarn derive from alteration of impure limestone, the alteration of high mud content of the clastic rock is weak.(2) Volcanic rock is found in Jxl formation with mineralization. That is a thin basalt-andesite rock interlayer in clastic-carbonate rocks of Jxl formation, magnetite is found between intersertal texture, that is in the gap of plagioclate grains of andesite. It is one of initial ore source of Proterozoic.(3) Determination of the ore-controlling structure and nature of the order. Ore bodies are bearing in the EW and WNW fault among the ore occurrence, it is consistent with the structure of occurrence. This group of main ore structure is conduit, but also a host space for ore body, belongs to compressive shear fracture. Post-ore structur have north-east and north-south two groups, belongs to estension shear fracture.(4) Forming temperature and fluid inclusion showed little variation range of gas-liquid ratio, as a miscible fluid; gas composition with H2O, CH4, H2, N2 mainly with the reduction of the initial fluid; uniform temperature of 130-300℃±, salinity (0.35～0.8)±wt% NaCl, the results from fluid inclusions, look for a typical low salinity and low temperature hydrothermal deposits.(5) Theδ34S of Weibao Pb-Zn deposit has lower value (3‰～5‰), it indicates that sulfur most from magma, meanwhile small portion came from Langyashan Group formation. The ratio of 206Pb/204Pb=18.04～18.63,207Pb /204Pb=15.33～15.52,208Pb/204Pb=38.11～38.72. According to Zartman's Pb isotopic scheme, most Pb isotope data are plot in the area between mantle evolution-trend line and upper-crustal evolution-trend, indicating that the deposit formed in a typical orogenic belt. Combination with lithogeochemical characteristics, we considered that the ore-forming materials were derived from the magma, meanwhile mixing by crustal, it show character of mixing between mantle and crust.(6) Indo-Chinese epoch hydrotherm replaced with carbonate and neutral-basic volcanic rocks of Jxlformation to derive skarns. The hydrotherm injects interlamination fracture, precipits sulfide ore. Succeeding hydrotherm activity leads superposition mineralization, including the invadation of diabase. The metallogenic model of Weibao Pb-Zn ore deposit is resemble with the Hutouai and Xiekeng deposits model.
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