oa Estimation of Permeability Structure with Self Potential Inversion

In this study, we developed the 2D inversion program that estimate the permeability structure from Self-potential (SP) profile. We applied these inversion programs to synthetic SP profiles. The synthetic SP profiles, used as observed data for the inversion, are evaluated with modeled slopes with 800m length and 40m height including various permeability anomalies. Four models including the permeable anomalies located in the center of the model are used for the estimation of the performance of our inversion. A priori information of the distribution of streaming current co-efficient, electrical conductivity and the flux volume at the discharge and recharge are given for our inversion. The horizontal zone with high permeability and the vertical zone with low permeability can be reconstructed with our inversion properly. However, the horizontal low permeable and the vertical high permeable zone cannot be imaged clearly. The regional groundwater flow pattern around the permeability anomaly has great effect on the SP pattern on the surface. The consideration of flow pattern around the permeability anomaly and effect on the SP profile are necessary for the accurate inversion of SP data.