基于四面体模型的地质体三维重建

3D reconstruction of geological body based on tetrahedron model

智慧矿山等数字化理念的提出,对三维空间数据的需求越来越多,同时对于地层模型也不再局限于直观的展示,更多需求在于地层属性及断层等地质结构分析处理。针对地质模型重建时缺少内部属性,以及断层等结构重建问题。以某矿区为研究对象探讨了体元数据结构下的地质三维重建。首先根据钻孔数据构建出合适的三维地质表面模型,对于断层部分借助局部法进行面模型的三维重建。然后对Tetgen算法进行编译得到Tetgen.a静态库文件,在此基础上对表面模型并进行封闭性、相交性等初始模型检验。调用库文件读取面模型的顶点,面片数据,借助剖分函数进行结构二次划分,从而完成将四面体模型重建。同时考虑四面体质量的前提下,调整剖分参数得到合适的边界纵横比,借此得到最优的四面体网格.从而完成了地质体以及断层结构体元模型的三维重建。借助某煤矿数据验证了该方法在地质建模的可行性,借助采集的巷道点云数据和采集的钻孔数据,利用四面体重建的方法完成地质层三维重建和断层结构的表达。结果表明以体元结构重建的三维模型能够对内部属性进行表达,同时对于断层等特殊地质结构也有较好的适用性,利用该方法完成的地质体重建,便于地质体的空间分析等后续应用为数字化矿山建设提供有利的数据支撑。

The proposal of digital concepts such as smart mines has more and more demand for three-dimensional spatial data, and at the same time, the stratigraphic model is not limited to intuitive display, but more demand lies in the analysis and processing of geological structures such as stratigraphic properties and faults.In view of the lack of internal attributes during the reconstruction of the geological model, the three-dimensional reconstruction of the geological structure under the volume data structure was discussed with a mining area as the research object. Firstly, an appropriate three-dimensional geological surface model is constructed according to the borehole data, and the three-dimensional reconstruction of the surface model is carried out by the local method for the fault part. Then compile the Tetgen algorithm to get the Tetgen.a static library file, on this basis, the surface model is tested for initial models such as closedness and intersection. Call the library file to read the vertices and patch data of the face model, and use the split function to divide the structure twice to complete the reconstruction of the tetrahedron model. Under the premise of considering the quality of the tetrahedron, adjust the split parameters to obtain a suitable boundary aspect ratio, thereby obtaining the optimal tetrahedral grid. Thus, the three-dimensional reconstruction of the geological body and the fault structure voxel model is completed. The feasibility of this method in geological modeling was verified with the help of a coal mine data. With the help of the collected roadway point cloud data and the collected borehole data, the three-dimensional reconstruction of the geological layer and the expression of the fault structure were completed by the method of tetrahedral reconstruction. The results show that the 3 D model reconstructed by the volume element structure can express the internal properties, and at the same time, it also has good applicability for special geological structures such as faults, and the reconstruction of the geological body completed by this method is convenient for the subsequent application of the spatial analysis of the geological body to provide favorable data support for the construction of digital mines.