Frequency domain soil parameters inversion of horizontally multilayered earth model with considering high-frequency field

A method to estimate soil parameters of horizontally multilayered earth model in frequency domain is developed with considering high-frequency field. The theoretical formula of complex apparent resistivity with considering high-frequency field is derived from Green's function. To avoid time-consuming numerical integration, complex image method is introduced to solve Sommerfeld integral. Simulated annealing algorithm is applied to optimise soil parameters. The accuracy of this method is confirmed by interpreting field data under the DC field. As the inversion results of this method are different from other literature's results in a four-layer model, the posterior analysis is made. Then this method is applied to the inversion of frequency domain soil parameters under both quasi-static field and high-frequency field. The differences of complex apparent resistivity distribution between quasi-static field and high-frequency field are compared at different frequencies.