Stratum Trend Surface Fitting And DEM Modeling

Three dimension stratum model provides a new approach for geology research so that the most commonly used two dimension figure and the three dimension information stored in the geologists' minds can be displayed by computer simulation. At the same time the corresponding stratum information inquiry can be implemented. In this way, geologists are able to further study the space distribution law and characteristic of geological body.In this paper, the commonly used surface modeling method and data fitness method are discussed, grid and fictitious column model is proposed based on a thorough analysis on current 3D space modeling method, This model was established on the foundation of drilling database, and it is expressed as the formal structure of Grid on the plane, fictitious column was set on the crossing of the Grid structure. The information on fictitious column was obtained by adding code to drilling histogram. An approach to modify the virtual pole is obtained utilizing the motherboard contour line gained during exploitation. The data interpolation used the method of weighted technology of moving trend surface fitting,the TIN structure interpolation,the weighted technology of moving trend surface fitting unified the TIN structure interpolation. Weighted technology of moving trend surface fitting gets over the weakness of trend surface fitting including fitting low and markedness is not obvious , and in the calculations using the R and F test decide the moving fitting radius and the size of weight of reference points, through adjusting the fitting radius and the weight of reference points to represent smaller deformation of stratum, at the same time ensuring the smooth linking of stratum and sufficient precision.The scan line algorithm has used in the TIN structure interpolation, this algorithm takes in the triangular net each triangle was researched object , then separately calculates in each triangle the all Grid points attribute value, The computation speed was faster of Grid point pertain in triangle.The weighted technology of moving trend surface fitting unified the TIN structure interpolation, the characteristic was used of weighted technology of moving trend surface fitting method production curved surface to have a better ductility and the TIN structure may the better retention stratum growth situation. The method has obtained a better effect.Adjusted the hypothesized column algorithm using the motherboard contour line data was to firstly topologize in the coordinated altitude region, then calculate point of rectification using profile line algorithm to make the special agreement on special situation of coordinated altitude shape. Meanwhile the paper carried on the classification to the shape of faultage, produced the method of description of different shape of faultage. The paper finally produced total design thought of grid and fictitious column model.