| Xishimen gold deposit locates in axis of Fuping mantle branch structure—mid-northern Taihangshan mountains, Southeast of Yanshanian Mapeng granitic intrusion, which genesis belong to the Epithermal lode gold deposit. Based on analysis of former data, through a lot of outdoor field geological survey and indoor data analysis, integrating regional mineralization geological background, geological characteristics of deposit, ore-control structure, ore-forming materials, genesis of granitic intrusion et al, this paper comes to some conclusions:(1) By the analysis of Au concentration of regional strata, which gold deposit is contained, it is close to or slightly higher than crustal abundance, and may provide some ore-forming materials, however, it is impossible to become main source beds for regional gold deposits.(2) Based comprehensive analysis on S, Pb, C, H, O isotopic composition, trace elements, fluid inclusion, it have shown that the ore-forming materials of gold deposits in this region should come from the deep interior of the Earth, with the multi-stage evolution of mantle plume, ore-forming fluids in the deep interior were moving upwards to shallow levels (crust). Because of sudden change of temperature, pressure et al, mixed with shallow fluid of crust, interacting with wall rock, ore-forming materials in the hydrothermal fluid precipitated, and enriched to form ores in the favorable tectono-metallogenic loci. During the multi-stage evolution of mantle plume, especially the ore-forming materials found their way into the crust vias the mantle, it is inevitable that some crustal material would have been involved. Therefore, the measured isotope data always fall between the typical mantle-source area and the crust-source area.(3) On the basis of petrochemistry, trace elements, rare earth elements of the Mapeng granitic intrusion, it is concluded that Mapeng granitic intrusion has a deep source, it is the product of the lower crust or upper mantle partial melting. Its genesis is syntectic type granite. It is one of representative granitic intrusion in the axis of Fuping mantle branch structure, also is product of multi-stage pulsating process of the intrusive magmatism, which lead to form typical multi-unit ringed complex spatially. Mapeng granitic intrusion has closely relationship with gold deposits temporally and spatially. It is also considered that Mapeng granitic intrusion plays an important role in the process of mineralization in this region: it linked deep ore-forming materials source, carried ore-forming materials upwards to shallow levels (crust), provided heat source for migration of ore-forming materials, and might provide some ore-forming materials for gold deposits.(4) From the statistical data of Au grade changes, which comes from currently mined four various levels, it can be seen that Au grade has a trend of decrease, with the mining depth increasing. However, the regularity can be found that the ore bodies often shows "beanpod-like" changes vertically, through statistical data of a large number of mines in Hebei Province, there may be another deep-seated "pod", therefore, mine should pay much attention to research on structure about mining area, providing necessary guidance for the next exploration of mine.
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