Two-dimensional Focusing Inversion Of Time Domain Induced Polarization Method Based On The Minimum Vertical Gradient Support

Time-domain induced polarization method is called TDIP ,It is a branch electrical method that based on the theory of IP effect in different rock and ore.Through the observation and research IP effect of earth, It is detect the conditions for underground geological. The traditional time-domain induced polarization method inversion methods are mostly based on minimum structure or smoothest model constrained inversion, Although the algorithm can stable convergence and eventually get the stable solution, The inversion results are not clear on the boundary of the abnormal body, The inversion results imaging resolution is not good, and the abnormal body positioning is not accurate, Therefore, it is not conducive to geological interpretation of late. In this paper, time-domain induced polarization method in minimum vertical gradient constraint inversion will improve these problems, The inversion results are more focused to the anomaly.In this article, forward research using finite element method, base on the existing studies of direct current resistivity, Using the principle of equivalent resistivity method, Improve the code and get the forward program of time-domain induced polarization method, Finally, We carry forward research to the model of the design by respectively using improved program and 3D finite difference of time domain induced polarization method, Compare the results of forward research and verify the correctness of the program.Base on the focusing inversion method by Zhdanov and two-dimensional MT data inversion base on the minimum vertical gradient support by Liu Xiao Jun,Introduce the minimum vertical gradient function, On the basis of data space inversion and minimum gradient functional,Combining the objective function for two-dimensional inversion of time domain induced polarization method, Derive the new formula and improve the code to achieve the purpose of this study. At the end, It design a consistent model and an inconsistent model of resistivity and polarization,The synthetic data are calculated by using different theoretical models, and compared with the traditional smoothing model constrained inversion results, It verifies that the algorithm can get stable inversion results, At the same time, It is also more accurate positioning of the abnormal body and more clearly on the boundary of the abnormal body, Inversion results are higher in imaging resolution, Focusing effect is more obvious. Therefore, it is further evidence that the reliability and validity of the algorithm.