1. Key Laboratory of Electromagnetic Radiation and Sensing Technology, Chinese Academy of Sciences, Beijing 100190, China; 2. School of Electronic, Electrical and Communicating Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
Abstract：Inversion is an important tool for transient electromagnetic data interpretation. This paper proposes a novel weighing scheme with periodic vibration for roughness restriction based on the regularized optimization theory. The small weights make the models sensitive to reflecting parameters' great changes and thus it is easy to show the thin layer with low resistivity. The large weights distributed near small weights can make sure the continuity of the inversion results, which reduces the variety of the solution. Synthetic models show that this method has higher resolution for low resistivity thin layer than traditional ones and keeps the same resolution with traditional ones when inverting low resistivity large areas. In addition, this method converges stably and does not rely on a prior information about the ground structure, thus making sure its application in practice.
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