| The research area where the Meng Man gold deposit which is in Meng Hai county, Yun Nan province lies, the tectonic structures lie in the fast south of Nu River-Lan Cang River-Jin Sha River(for short 'the three river') fold system. 'The three river' area is our country's important metallogenic province which contains kinds of metal minerals. 'The three river' basin and its dependent transecting mountain range, including southeast of Qing Zang plateau, Dian Xi and Dian's southwest plateau, which are retained by mainland's three big tectonic units from the mesozoic era, and are endured the strong lateral turning effect by Qing Zang plateau's crustal material towards the SSE direction, this specific tectonic structures background and regional structure stress field make this area forming a quite complicating structure prospect after multi-phase structure actions.The bearing ore stratigraphic lithology unveiled in the research area include upper Proterozoic erathem Lan Cang Group Man Lai Group metamorphosed rock series, Middle Jurassic Series Hua Kai Zuo Zu clastic rock series and the Quaternary period weathering slope eluvium. Gold mineralization can be divided as micro fine type(that is Carlin type, gold mineralization lies in the lower basement rock series) and lateritic type(gold mineralization lies in the upper residual-slope sedimentary rocks) according to the producing position, stratigraphic lithology and ore genesis. This thesis discusses the source of Gold deposit's metallogenic materials through elemental geochemistry, isotope geochemistry and geochemical thermodynamics calculation.Through the research, it finds that Meng Man Gold Deposit is a sedimentary reformatic low-temperature hydrothermal micro fine type gold deposit. The research area belongs to fault structure, the gold deposit mainly distributes along some big fractures in the research area. Through the research of geological features of ore deposit, ore controlling geological condition and ore substance composition, it regards that this gold deposit does not have the typical strata-bound characteristic, and combining with the silicon isotope geochemistry and silica cathode luminescence research method to track the silica source have proved successfully that mineralization silica is not provided by surrounding rocks, that is , the gold deposit mineralization of Meng Man is controlled by the regional geotectonics'development and evolution, the formation of the gold deposit is closely connected with the deep fracture zone and hydrotherm activities.The research area H-O isotope date show that the date ofδD‰is -91～-94‰;the date ofδ18OH2O‰is 0.01～1.18‰,the date of Pb show that the range of Pb206/Pb204 is 18.496-18.706,the range of Pb207/Pb204 is 15.592-15.677,the range of Pb208/Pb204 is 38.621-38.959c The research area S isotope (δ34S‰) is make up of iron pyrites,the date of S isotope is -2.194±0.003‰～-2.974±0.005‰,the average date of S isotope is -2.638‰。Through the research, it regards that the resource of Meng Man gold deposit metallogenic materials are mainly from Yan Shan advanced stage upper-mantle hydrotherm. Yan Shan advanced stage(Yan Shan tectonic stage) after Middle Jurassic, this area erupted strong orogenetic movements once more, making the original closed deep fault revived again, and forming super crust deep fracture, it makes the differential ore-forming fluid aggregated on deep upper mantle crossing the crust-mantle interface, then entering into crust; however, when fluid crosses the interface, because of the interaction of high pressure and steam which make the Au in fluid showing as nanometer grade powders natural gold colloidal particle. With Yan Shan motion development's deep magmatic activity(it provides heat dynamic resource for ore-forming fluid transaction, not ore source) and contemporaneous fault tectonic activity, they make the those ore-forming fluid distribute in the sedimentary strata in a way of exhalative sedimentation, with a result, the upper part preliminarily enriched along with the fracture, interlayer structural belt and unconformity surface controlling sedimentary strata, thus, it forms massive ore containing construct. Gold content in the this research area which is along with the structural belt, and which is in Middle Jurassic Hua Kai Zuo Zu distributes on the upper and lower unconformity surface and Man Lai group's gold content in the background of this tectonic structure and the mineralization, it becomes more rich on the basis of the original ore source bed, thus, it forms the Meng Man Gold Deposit nowadays.Through this paper research,we have a basic understanding about this areas's Ore-forming Meterials,this understanding guides next step's ore-finding in theory and practice.
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