| Fankou Pb-Zn ore deposit is one of the famous super-large Pb-Zn deposits in China. It is situated on the north of Quren structural basin in Nanling mineralization belt. Directed by the genetic mineralography and genetic mineralogy, based on the macro-geological research, firstly, some mineralograph properties of ore, such as ore type, ore composition, texture and structural feature, characteristics of mineral generations, mineral assemblage in Fankou Pb-Zn ore deposit have been researched. And the stage of mineralization and mineral formation order of this ore field was obtained. Secondly, based on X-ray diffraction, microprobe analysis, homogenization temperature and composition measurement of fluid inclusions and sulphur isotopic composition measurement, some genetic mineralogical properties of lead-zinc sulphides (especially sphalerite) have been studied. It provides new data for the prediction of depth and margin prospecting in the mining area. Thus, this contributes to the work of new round of prospecting in this area. The major cognition is as follows:1. According to the characteristics of texture and structural feature of ore, mineral assemblage, mineral generations and mineralized wall rock alteration in Fankou Pb-Zn district. Without considering the changes of supergenesis period, the whole sulfide ore mineralization process is classified into two metallogenic period and three mineralization stages. Two periods are sedimentary diagenetic period and hydrothermal metallogenic period. Three stages are the early pyrite mineralization stage, middle temperature lead-zinc sulphide mineralization stage, and low temperature lead-zinc sulphide mineralization stage.2. From the characteristics of ore fabric and mineral assemblage in representative ore-bodies, it can be discovered that multi-stage mineralization in Fankou ore district is significantly. Among them, sphalerite has three generations:the first generation of brown-black sphalerite, the second generation of brown sphlerite, the third generation of yellow-brown sphalerite. Galena also has three generations. And the pyrite in ore-body at least has four generations.3. According to the iron content of sphalerite, the homogenization temperature of sphalerite fliud inclusions.δ34S fractionation equilibrium temperature of sphalerite and galena, it is considered that the mineralization of lead-zinc sulfide in Fankou ore district occurred in middle-low temperature environment. But with the evolution of mineralization, from the early stage to the last stage, the temperature varied from low through high to low again, in which the cooling process is more significant.4. The compositions of ore-forming fluid in Fankou Pb-Zn ore deposit is Na+-Cl-SO42-.The value ofδ34S decreased, but the decreasing was much more drastic from the second to the third stage than from the first to the second stage, implying that a portion of newly-produced solution with much lower values of 834S participated in the ore-forming fluid during the third stage.
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