The 3D Shape Simulation And Metallogenic Geodynamic Computational Modeling Of Dongguashan Copper Deposit In Tongling

The metallogenic system is complex in spatial structure and temporal process. The computational modeling is the most effective method for revealing its shape and structure and replaying its geodynamic processes. In this thesis, the Dongguashan copper deposit, as the largest copper deposit in the Yangtze River Metallogenic Belt, was studied through 3D shape simulation and computational modeling of its metallogenic processes. By using of the GOCAD code,3D geological models are constructed through discrete smooth interpolation and triangulated irregular network. By programming, the SGrid model of GOCAD is transferred to the hexahedron-mesh model of FLAC3D. Based on the geological investigation, the 3D geodynamic model involved the coupled mechano-thermo-hydrological processes is constructed and computed by numerical method, of which the results are analyzed to extract the implication for dynamic mechanism of ore-formation and ore-controlling factors. The main outcomes in this thesis include the following 4 aspects.1) The 3D shape of the main ore body and the spatial relationship of the main ore body with other geological factors are revealed by 3D geological modeling, and it is discovered that the main ore body is controlled by both the anticline and the intrusion.2) By systematically summarizing the algorithms of 3D mesh generation, the current situation and development trend of the mesh generation and its application in the geosciences are analyzed.3) The complex 3D geological model is transferred to the FLAC3D model through programming the transferring of the SGrid model of GOCAD into the hexahedron-mesh model of FLAC3D. It is successfully used to model the geodynamic processes of the metallogenic system in the Dongguashan copper deposit.4) The results of the geodynamic computational modeling experiments demonstrate that, the ore formation is closely associated with coupled geodynamic processes during the syn-tectonic cooling of the intrusion, and the coupled mechano-thermo-hydrological processes result in the generation of the fluid-focus dilation zone in the carbonate of the medium to upper Carboniferous, favorable for forming the stratum-bound ore body.