The Key Technology Of 3D Geological Modeling Research

Building and displaying a geologic model is one of the core content of 3D geological modeling process, is also a difficulty and a focus of research. Not only embodies in a good geological model can accurately describe the structure of the geological objects, attributes, spatial distribution and other kinds of complex features, but also conducive to geological action and analysis. At present, the voxel modeling method and surface modeling method is to build 3D geological model of two methods of the mainstream, but its theoretical knowledge is not very mature. Such as the modeling ideas, key technologies are the content of the need to further research, improvement and perfection.Two key problems are studied of the paper are building a three-dimensional closed block model method and turn closed block model into grid model.The purpose of building block model is to make up the defects of surface model that can’t show the formation characteristics. According to the structure characteristics of the surface model, this paper puts forward that the approach is based on 3D surface model block tracking to build and the corresponding closed block model, which is put by the surface of each individual find enclosed formation blocks all out. Paper designs and realizes two different ideas of three-dimensional block tracking algorithm, accurate block tracking algorithm and fuzzy block tracking algorithm. Accurate after block algorithm is the use of surface triangulation network topology relations and the intersection of a clear correspondence between two surfaces to track of block, adapted to the topological consistency of surface model; Fuzzy after block algorithm has high fault-tolerance, its basic idea is first divided into the space interval, such as three-dimensional grid, roughly track first made of the cube grid block, reuse ray discriminant method to find block the outer boundary of a triangle, thus adapted to the topological consistency of surface model. Paper is tested to this algorithm, and through its successful build their applicable under the surface model of the corresponding closed block model.The purpose of building grid model is to make up for the block model to space operation and the analysis of the defects. Papers on the grid of some kinds of commonly used body yuan has made the detailed analysis and comparison, and to learn about the Delaunay tetrahedron is physical structure, a good space has many excellent mathematical properties, therefore put forward using the Delaunay tetrahedron as the basic unit of grid model; Block in the model at the same time every single block body is closed, so you can by capping the Delaunay tetrahedron subdivision algorithm to model each of a closed block separately to grid is constructed and the matching formation block grid model. Paper to limit the Delaunay tetrahedron subdivision algorithm has carried on the thorough research and analysis, this paper introduces the one with the core of the tetrahedron grid generator TetGen, and by using the TetGen multiple complex closed tetrahedron grid block model test, and according to the results of the final subdivision map their corresponding grid model, and it also has good quality of grid.