Research On Key Technologies Of Three-dimensional Complex Geological Surface Reconstruction

As the basis of geological modeling,reservoir simulation and geological structure mapping,Geological surface reconstruction mainly uses geological data such as seismic interpretation data,well logging data and aeromagnetic data to construct geological surface combining the theory and method of computer graphics,thus it plays an important role in the field of underground resource exploration.Unlike general surface reconstruction methods,there are many limitations and complexity in the reconstruction of geological surface.First of all,the data used for the reconstruction of geological surface is sparse and unevenly distributed.Secondly,many geological attributes tend to have strong trend or anisotropy,and the collected geological data are often in line shape.Geological surface reconstruction based on these data usually failed to reflect the tendency of geological attributes.Finally,complex geological structures often contain folds,reverse faults or mushroom-type intrusions,and so far there is no complete reconstruction algorithm for such unclosed multivalued surfaces.Therefore,there are many difficulties and challenges in the reconstruction of 3D complex geological surface.In this paper,extensive surface interpolation methods are studied,the characteristics and applicable conditions of different interpolation methods are analyzed,specially,Kriging method and DSI method are applied to the reconstruction of geological surface.In order to improve the efficiency of traditional Kriging interpolation method,an improved Moving Neighborhood Kriging method is studied and implemented.Furthermore,aiming at the issue of uneven distribution of discrete points in the reconstruction of geological surface,an anisotropic interpolation method based on Taylor formula is studied and implemented.Through model test and comparison with other common surface interpolation methods,it is shown that this method can accurately present the anisotropic characteristics of geological attributes,To a certain extent,it avoids the beaded structure defects of traditional geological surface interpolation methods;for the construction of unclosed multivalued surface,it studies and implements a method of multivalued surface reconstruction based on Delaunay growing method,and the unclosed multivalued surface reconstructed by this method tend to have a better topological shape,also the algorithm has a higher execution efficiency,but it is easy to produce topological errors such as holes and triangles crossing in the region with large slope.In order to fix topology errors caused by the algorithm when reconstructing non-closed and multivalued surface,a new method based on Euler formula is proposed to detect and repair topological errors in the reconstruction of non-closed multivalued surfaces.Examples and comparison with conventional algorithm illustrate that the method based on Eluler formula can identify the boundary of unclosed surfaces and holes automatically,and is able to repair the topological errors such as holes and the intersection of triangles on the unclosed surfaces.