Construction And Application Of Complex Geophysical Model Of Dongguashan Cu Deposit In Tongling District

Currently,the forward and inversion technology based on unstructured tetrahedral grids has the ability to approximate any undulating terrain and specific geological structures.However,it is very difficult to build tetrahedral grids of arbitrary complex geological models,which restricts the application of this technology in actual exploration.In response to this problem,we proposed a set of modeling procedures for complex geological-geophysical models,developed a series of modeling codes and software interfaces,and developed a series of modeling codes and software interfaces that integrate digital elevation data,geological profiles and borehole data and other geological and geographic information.The ability to efficiently build high-quality complex geophysical models for finite element simulation calculations.The three-dimensional geological model is a visual digital model that expresses the contact relationship between various geological elements,and is the basis of geological research.The 3D geophysical model is a quantitative calculation model that represents the underground geometric interface based on grid cells,and its essence is a regular numerical sequence of grid nodes,topological relationships and physical property values.Although there are differences between the two,their geometric interfaces are constructed by two-dimensional discrete meshes.Therefore,the 3D geological model can be converted into a 3D geophysical model by using the 3D meshing technology.This paper proposes a set of complex geological-geophysical model modeling process,which starts from the multi-source data fusion modeling method,uses SKUA-Gocad modeling platform and Facetmodeller software to build a 3D geological model,and then builds a3 D geological model based on constrained 2D/3D-Delaunay meshing algorithm,to optimize the interface triangular mesh quality,local mesh refinement and interface mesh constraint resampling for the 3D geological model,so as to establish an integrated 3D volume model,and finally use Tetgen meshing The generator generates high-quality tetrahedral meshes for finite element calculations.This process has higher modeling efficiency,wider applicability,and easier model modification,optimization and quality control.In order to verify the applicability of the modeling process proposed in this paper,we take the Dongguashan copper mine in Tongling as an example to establish a high-quality complex geophysical model,and use the previously derived tetrahedron-based analytical solution formula and finite element algorithm Gravity-magnetic,magnetotelluric(MT)and wide field electromagnetic method(WFEM)responses of the model are calculated.A series of forward calculation results show that the modeling process proposed in this paper has high applicability,the established geophysical model has good grid quality,can meet the stable calculation of different algorithms,and has a wide range of potential applications.The new modeling technology proposed in this paper can not only be used to eliminate the interference of known shallow geological bodies in mines,but also provide a high-quality reference model for deep data inversion,thereby improving the effect of deep exploration.Figure 38;Table 6;Reference 86...