Implicit and automatic modeling method for complex coal seam geological bodies integrating fault potential fields

ZHONG Deyun; WANG Liguan

doi:10.13225/j.cnki.jccs.2024.0969

Abstract：In the construction of coal transparent geological systems,automatic modeling of coal seam geological bodies with complex cross-fault networks and dynamic updating of models is a challenging task.To solve the geological model-ing problem of coal seams with complex fault networks,based on the non-stationary geostatistical theory and implicit modeling potential field interpolation theory,a Radial Basis Function(RBF)interpolation theory with additional external drift and a three-dimensional automatic modeling method are proposed for coal seam geological body with additional fault potential field.The proposed implicit modeling method consists of the following steps.In terms of fault interpolation con-straints,the theory and method of radial basis function interpolation that integrates fault potential fields are proposed by deriving the formula for radial basis function interpolation that integrates external drift.In terms of fault potential field representation,the fault line potential field is introduced for the first time to define the range of fault influence,which can interpolate the discontinuous interpolation trend and smooth transition trend between different types of faults and coal seams.In terms of defining fault networks,a directed graph is used based on graph theory to represent the topological rela-tionships of mutual influence between fault networks,and then a combination of fault potential fields is constructed to define the truncation intersection relationships between fault networks.In terms of model surface reconstruction,the Con-strained Delaunay Triangulation(CDT)method that ensures geometric accuracy is used to achieve feature preserving inter-polation and reconstruction of fault lines,ensuring reliable Triangulated Irregular Network(TIN)mesh models with impli-cit surface reconstruction without the need for mesh post-processing operations.Based on the above methods,an automat-ic modeling system of three-dimensional coal seam geological body model was developed for the coal geological assur-ance system.The system supports the automatic construction of complex fault network topology relationships,which can greatly improve the efficiency of implicit modeling of coal seam geological bodies.In order to test the interpolation effect of the radial basis function interpolation method incorporating external drift and the modeling effect of the coal seam geo-logical body modeling method incorporating fault potential field,the reliability of the implicit modeling method incorpor-ating complex cross faults of the coal seam geological body has been verified on the basis of real datasets from several mines.The proposed method can efficiently and automatically model complex coal seam geological bodies with a large number of different types of cross fault networks,and satisfy the geological rule constraints such as the fault motion char-acteristics and the influence range of the faults,which is an important application value for the accurate modeling of coal seam geology.