An adaptive sharp boundary inversion scheme is developed to improve resolution with feasibility for transient electromagnetic (TEM) data inversion. By using weighted minimum gradient support (WMGS) constraint, this method focuses the resistivity change areas on layer boundary locations. Prior information describing roughness can be added into the constraint to improve resolution. Furthermore, even though no prior information about layer boundaries is available, it can still reconstruct models with geo-electrical interfaces. Synthetic models prove that this method has a better performance in presenting layer boundaries than smooth-model inversion. Field data of a TEM test line are inverted using this method, which makes the basement layer visualized easily.
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