| The Yingchengzi gold deposit was located in the southeast of Xiaoxing'anling-zhangguangcailing magma fole balt and the south of vocalnic-magma belt which was in the eastern margin of Xing'an Mongolian orogenic belt which was between North China Plate,Xingkai Block and Kiamusze Block. In the eastern of mining area developed the Mudanjiang Fault which was north-south tendency, the Dunmi Fault was in the south of deposit. Luwei river petrofabric and dama river petrofabric was the oldest stratum in the area; magmatic rock was developed, the most of the rock is instructive rock of Caledonian, Hercynian and Yanshanian. Because of the Dunmi Fault developing in the Cenozoic, so there was a lot of alkli basalt in the mining area. But the abordest distribution is the Yanshanian granite, which had the most closed relationship with the deposit in the area.The research area was a archipelatic ocean between the Siberia Plate and North China Plate, there was three small block, Erguna-xing'an block, Songnen-zhangguangcailing block and Kiamusze block, distributed in the archipelatic ocean in the intermediate and advanced of Proterozoi. In the palaeoproterozoic, Paleo-Asian Ocean begin to expand, the oceanic crust occurred strong strike-slip subduction which was last out Silurian while the Paleo-Asian Ocean closed. In this period, strike-slip connection was occurred between the Kiamusze block and Songnen block, there was large-scale magma instructive and strong ductile deformation in the course. The Yingchengzi adamellite which was the enclosing rocksite and the eastwest trend ductile-brittle shear zone which controlled the orebody distribution were formed in this process.The Yingchengzi gold deposit hosted in the eastwest trend ductile-brittle shear zone(mylonite zone). There was 18 strip orebody, the most shape of the orebody is lenticular, besides there was layered and stratiform-like. The most mineralization of the deposit is sulfide altered mylonite type, a small quantity of the orebody was sulfide quartz vein type. By the field and laboratory study, the most ore minerals were pyrite, chalcopyrite, sphalerite and pyrrhotite, the lesser ore minerals were arsenopyrite, bornite, hematite and galena; the gangue mineral were quartz, goethite, chalcocite, covellite and malachite et al..Base on the correlation of the minerals and ore fabric, we divised the mineralization stage as: quartz- arsenopyrite- pyrite sulfid stage(>350℃), quartz- pyrite stage(250℃~300℃), polymetallic sulfide stage(150℃~220℃) and quartz- sulfide stage(100℃~150℃).The most fluid inclusion type of Yingchengzi gold deposit was gas-liquid phase inclusion, small quantity types were gas phase, liquid phase and three phase inclusions. The shape of inclusions were elliptic, long strip and irregular, the size was between 4-10μm, the gas-liquid ratio was 10%-30% and 40%-50%; homogenization temperature between 100℃-450℃, the different mineralization stage had different homogenization temperature; w(NaCl)/% of inclusions between 3-13%, belong to medium-low salinity; the character of Laser Raman show, gaseous compositions were CO2,H2O and CH4, small quantity of organic compoents, such as C2H6 et al. As a whole, the ore-forming fluid had mantle-derived fluids characters, belonged to CO2-CH4-H2O system.Studying the major elements, trace elements and isotope element of the yingchengzi adamellite and vein rock which had a close relationship with orebody, the result showed that both were high potassium calcium-basicity rock which occurred in active continental margin. Yingchengzi adamellites showed some crust-mantle mixed source character, the crust matter were in the majority; the vein rocks showed intense mantle-derived characters, only contaminated with some crust matter. Combined with the character of trace elements ,Pb isotopeand ore-forming elements of orebody and vein rock, we considered the metallogenic materials were from lithosphere, mixed with little mantel substance. The U-Pb zircon ages showed yingchengzi adamellite's age was 476±5.5Ma, vein rocks'age was 430±15Ma, indicated their ages were in accordance with the Paleo-Asian Ocean subduction(471.23±58.63Ma) and strike-slip connection between the Kiamusze block and Songnen block(445.36～414.65Ma).From research result of the ore-forming fluid, metallogenic chronology, ore-forming material source and metallogenic environment, showed that because of the Paleo-Asian Ocean closed, Kiamusze block and Songnen block occoured strike-slip connection in the Paleozoic, a large scale magamtism which formed a mass of granite in the mining area was occurred in this period. The intense collision produced the eastwest trend ductile-brittle shear zone in the deposit. The strong ductile deformation made the initial ore bearing fluid which was mantle-derived and the magma of vein rock ascend along shear belt, meanwhile some matters was activation and interfused with the initial ore bearing fluid because of the deformation of around of granite. In transfer sites of toughness and brittle, because the physicochemical condition changed, ore-forming material occoured deposition forming lentoid altered mylonite type ore-body. In the continuous transport of some ore-forming fluid, some infiltrated atmospheric water maybe mix with the ore-forming material forming a spot of sulfide quartz vein type ore-body.Compared Yingchengzi gold deposit with some type domestic and overseas'orogenic gold deposits, we found they had some common departments in metallogenic characteristics, belong to related to orogenic belt gold deposit. So, we concluded Yingchengzi gold deposit was a middle temperature geotherm gold deposit that was related with orogenic belt, which was formed in the active continental margin, and its direct thermodynamic was mantle-derived magma which was formed by the Paleo-Asian Ocean subduction and the oceanic crust dehydration melting.
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