Interpretation of self-potential anomaly over 2-D inclined thick sheet structures and analysis of uncertainty using very fast simulated annealing global optimization

Abstract

Global optimization for the interpretation of Self-Potential (SP) anomaly using a very fast simulated-annealing (VFSA) inversion code is developed in the present study. The SP anomaly is measured over a 2-D inclined thick sheet-type electrostatically polarized structure. Different model parameters for thick sheet-type structures are optimized. VFSA optimization yields a large number of well-fitting solutions in a huge model space. Uncertainty in the interpretation is analyzed and the study shows that it remains in few model parameters. The efficacy of the developed approach has been demonstrated using noise free and noisy synthetic examples. Field data from three different regions is interpreted for multiple thick sheet-type structures related to mineral exploration. The computation time for finding this convenient solution is very short (100 s for single structure) and the proposed method is found to be useful for interpretation of thick sheet-type structure and for multiple bodies as well. The interpretation procedure can be used for assessing mineral deposits as well as the SP of the earth’s crust.