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.Characteristics of the static shift are discussed by comparing the three-dimensional MT inversion with/withoutstatic shift parameterization. The galvanic distortion by small-scale shallow feature often leads severe distortion in invertedresistivity structures. The new inversion algorithm is applied toof static shift. In real field data interpretations, we generally do not have any a-priori information about how much thedata contains the static shift. In this study, we developed an algorithm for finding both Lagrangian multiplier forsmoothnes and the trade-of parameter for static shift, simultaneously in 3-D MT inversion. Applications of this inversionroutine for the numerical data sets showed quite reasonable estimation of static shift parameters without any a-prioriinformation. The inversion scheme is sucesfully aplied to all the four data sets, even when the static shift does notobey the Gaussian distribution. Allowing the static shift parameters have non-zero degree of fredom to the inversion,we could get more acurate block resistivities as well as static shifts in the data. When inversion does not consider thestatic shift as inversion parameters (conventional MT inversion), the block resistivities on the surface are modifiedblocks on the surface can generate the static shift at lowfrequencies. By those mechanisms, the conventional 3-D MT inversion can reconstruct the resistivity structures to someextent in the deeper parts even when moderate static shifts are in the data. As frequency increased, however, the galvanicdistortion is not frequency independent any more, and thus the conventional inversion failed to fit the apparent resistivityand phase, especially when strong static shift is added. Even in such case, however, reasonable estimation of blockresistivity as well as static shift parameters were obtained by 3-D MT inversion with static shift parameterization.