Application Of Antisotropic Diffusion Filtering In 3D Seismic Data Processing

Seismic data processing is the premise of seismic data interpretation. In thepractical exploration process, the real seismic data include various noises, thusaffecting the quality of seismic data. Therefore, it is very important of inhibit differentinterference and improve signal-to-noise ratios and the quality of seismic data. In 3Dseismic data processing, in order to improve the quality of seismic data and protectgeologic boundary, we need filtering method that can explore like faults geologicalbody boundary.This thesis based on previous studies, structure tensor is introduced to extractlocal structure information of 3D digital image or 3D seismic image. There structureinformation was discussed through geometric features and geological structures.According to seismic image structure characteristics, combined confidence measureand stratigraphic coherent coefficient, designed eigenvalues of diffusion tensor, andconstructed the diffusion tensor to control diffusion rate of three main orientations.Through solving the partial differential equation, realize 3D digital image anisotropicdiffusion filtering, and also applied successfully to the process of 3D seismic filtering.Main works are as follows.(1)Take on anisotropic diffusion equation proposed by Weickert and 2Danisotropic diffusion on basis, collects and arranges literature and material of digitalimage filtering, and illustrate the 3D anisotropic diffusion filter method basicprinciple.(2)Through tensor product point gives structure tensor definition, usestructure tensor extract local structural information of digital image. Fromcharacteristics of the digital image structure, discuss the image planar linear structureand line linear structure characteristics, and analyze the relation between eigenvaluesof the structure tensor and digital image structure features. According to these relations, design eigenvalues of diffusion tensor, control diffusion rate of three mainorientations, achieve the purpose of the anisotropic diffusion.(3)Give solving method for 3D images structure tensor and constructionmethod of diffusion tensor, and derive detailedly discrete equations of anisotropicdiffusion equations, and design algorithm of 3D anisotropic diffusion filtering, andrealize the filtering algorithm programmed in MATLAB and c++ language.(4)According to common geological structures in the seismic data processing,build corresponding 3D geological model. The results of 3D noise model test haveverified the correctness and effectiveness of anisotropic diffusion filtering.(5)Real 3D seismic data processing includes anisotropic diffusion filteringachieves the expected effect. This method can inhibit coherent noise, enhance thecontinuity of seismic phase axis, and effectively keep fault, river information.3D anisotropic diffusion filtering method can improve the SNR of seismic dataand the quality of seismic data, can make the fault or geological boundaries clearer,and help to further treatment and seismic data interpretation.