Research Of Complex Geological Structural Modeling Based On Sparse Point Cloud Surface Reconstruction

Structural geology modeling play an important role for the exploration of oil and gas resources. Structural modeling is based on the structural interpretation data, through the geological curved surface fitting, finally, form the geological framework modeling with the boundary of the horizon and fault surface. And structural modeling provides basic constraints to describe the geological characteristics, the sequence modeling, lithology modeling, reservoir description framework, etc. For computer graphics, geological curved surface fitting is a question of point cloud surface reconstruction. Unlike existing point cloud surface reconstruction, structural interpretation data is sparse and complex, sparse sex refers to an imbalance in the spatial distribution of the tectonic interpretation data, relatively concentrated in the seed section direction, and the distribution is sparse in the other direction; Complexity refers to as a result of the existence of fracture structure and reverse structure, lead to geological curved surface in XOY plane projection overlap areaThe author of this paper studies the problems of the above-mentioned two aspects in the Complex geological structural modeling, this paper put forward a method of sparse point cloud surface reconstruction based on the logic of the neighborhood and complex geological structure modeling method based on projection plane, the main work is as follows:(1) It proposed sparse point cloud surface reconstruction method based on logical neighborhood. In geological field, the original point cloud of uneven distribution is serious, the original seed point in the direction of the line data distribution is relatively dense, and the seed point on the other direction is very sparse. Compared with traditional physical neighborhood surface reconstruction method, because of the connection of Delaunay triangulation, the search method based on the logical neighborhood makes the interpolation result more accurate because the interpolation points are in all directions, and the curved surface fitting effect is better.(2) It proposed the method of the complex geological structural modeling. The original seed point data are projected to a vertical projection plane, Delaunay triangulation network is connected in the plane, so we can get the spatial triangulation network through the one-to-one correspondence relationship of the seed point and the projected point, namely complete overturned fold surface reconstruction. And we can transform the selection of the projection plane problem into an optimization mathematical model, use the two ways to gain the effective range of the projection plane, and then it is converted to convex optimization problems and it is solved on the basis. After generating geological horizon model, and finally to closed side to get three dimensional geological block model, namely the complex geological structure modeling is completed.To sum up, in the geological field, the method which is based on the logic of neighborhood sparse point cloud surface reconstruction can solve the problem of original sparse seed point data, and the surface effect by this method is good, for the method of complex geological structural modeling, this paper puts forward the idea which is based on the projection plane and has obtained the good effect, and it provides a new train of thought for complex geological structure modeling.