Magnetotelluric Method And Magnetotelluric Method Considering The Influence Of Permeability Two-Dimensional Joint Inversion

In this paper,case studies have been carried out on the geophysical joint inversion method theories that have become more popular in the field of geophysics in recent years.First of all,in a single two-dimensional inversion of the magnetotelluric method,the magnetic permeability is synchronized with the resistivity,and then conducted theoretical research work on the two-dimensional joint inversion of magnetic data and magnetotelluric method.Joint inversion is a favorable direction for inversion of geophysical inversion by simultaneously inverting the physical structure of the underground by the physical properties of the geological body and the interrelationships between the geometric parameters.Inversing multiple physical parameter data at the same time during inversion The physical property parameter data,which uses the physical property relationship constraints,is different from the single geophysical inversion method.It can not only overcome the limitations of adopting an inversion strategy alone,but also reduce the inversion process from the problem of multiplicity.In terms of magnetic methods,this paper adopts analytical methods to solve forward anomalies of magnetic anomaly.The two-dimensional inversion of magnetic method data adopts the application of smoothness constraints and logarithmic barrier methods to avoid reciprocity when Gauss Newton method is used to invert susceptibility.The existence of negative values reduces the multiplicity of solutions in the magnetic inversion process.This paper introduces the model smooth term,logarithmic obstacle term,and data fitting difference to improve the objective function to constrain the model in the objective function of the magnetic method inversion..In the field of magnetotellurics,the magnetotelluric forward response considering the magnetic permeability adopts the finite difference method for solving,and the twodimensional magnetotelluric inversion selection adopts the nonlinear conjugate gradient method for the simultaneous iteration of the two parameters of permeability and resistivity.Calculate the model update amount,and add the model smoothness to the objective function to increase the constraint effect of the objective function on the model.In the process of joint inversion,this paper based on the cross-gradient theory(Gallardo & Meju,2004)constrained the realization of the two-dimensional joint inversion of magnetotelluric data and magnetotelluric data considering the magnetic permeability,and carried out the influence of the positive and negative inversion.The model example test improves the applicability and credibility of the inversion method of this paper.