Nonlinear Joint Inversion Algorithm Research Of DC Resistivity And Rayleigh Wave Seismic

Currently the electrical method and Rayleigh wave seismic method used in the near-surface geophysical played an important role in the Environmental and Engineering Geophysical. These exploration methods including forward and inversion theory, explain the methods and applications are gradually improving. However in the inversion process, it is necessary to adopt a joint inversion by adding constrains to reduce the multiplicity. This dissertation proposed artificial bee colony algorithm for multiple methods of inversion, studied joint inversion of many methods to overcome the multiplicity to improve inversion accuracy and efficiency.First of all, detailed analysis of principles, methods and forward modeling theory of DC resistivity sounding method, high-density resistivity method and Rayleigh wave method, using Matlab respectively programmed the forward modeling of DC resistivity sounding, High-density resistivity and Rayleigh wave mothod, which used linear filter algorithm in DC resistivity sounding method, used limited unit algorithm in High-density resistance rate law, used speed scalar transfer algorithm int Rayleigh wave. Fitted for the two-story, three-story, four-story model of the one-dimensional geological model and the single low resistance, one high and one low double resistance, mixed abnormal model of the two-dimensional geological model and analyzed the fitting results. These works provided preparation for inversion.Second of all, based on the artificial bee colony algorithm principle, established suitable non-linear inversion objective function of the artificial bee colony algorithm according to the respective principles and characteristics of DC resistivity sounding, high-density resistivity method and Rayleigh wave method. Through experimental analysis, chosen the best combination of parameters for a variety of inversion methods, and used Matlab respectively programmed nonlinear inversion algorithm based on artificial bee colony algorithm for DC resistivity sounding, High-density resistivity method, the first model of Rayleigh wave, and studied Rayleigh wave multi-stage mode joint nonlinear inversion algorithms, electrical sounding and first mode of Rayleigh wave joint inversion algorithm, electrical sounding and Rayleigh wave multi-stage model joint inversion algorithm. After calculating the theoretical model, obtained the conclusion that inversion model based on artificial bee colony algorithm has the advantages of stability and promotional.Finally, validating by Hebei Chengde Civil Airport Exploration Project, the results showed that joint nonlinear inversion method of the electrical sounding and the Rayleigh wave based on artificial bee colony algorithm has effectively solved the problem of multiplicity of a single method, and has convergence rate, better fitting and generalization.