An Optimization Method for Interpreting ERT Data Based on Groundwater Numerical Modeling (Which Data Polarization Mode Should Be Used in 2D Inversion)

Abstract

Aiming at choice of data polarization mode in magnetotelluric 2D inversion, trying to assist the geophysical inversion with the hydraulic characteristics of the water level and water quality information contained in the geological body. Based on this idea, a method for interpreting ERT data based on groundwater numerical modeling which data polarization mode should be used in 2D inversion is provided in this article. In this article, Magneto-telluric method as a way to accomplish numerical simulation of geophysical forward and inversion. Firstly, by studying the known geological model and multiple geological models with different choice of data polarization mode interpreted from ERT data, a set of groundwater numerical models can be set up. Then numerical simulation of groundwater flow and solute transport were conducted. Lastly, the optimal data polarization mode can be obtained by comparing the result of numerical simulation of groundwater. Sensitivity analysis were also conducted to verify the method. And the result show that the inversion model using only TE mode data is more valid, next is TE + TM, TM mode only is not proposed by comparing the numerical value of Standard of the Estimate, Root Mean Squared, Normalized RMS and Correlation Coefficient.