Three-dimensional magnetotelluric inversion regarding distortion tensors as unknown parameters

Negi, Tateyuki*; Makuuchi, Ayumu*; Hama, Yuki; Asamori, Koichi

In magnetotelluric (MT) soundings, Galvanic distortions, which might disturb the reliability of the resistivity model estimated by inversion analyses, are often recognized. In order to solve this problem, we developed a new three-dimensional MT inversion method that can estimate both resistivity model and distortion tensors without prior information. Using synthetic examples of data under distorted and noisy conditions, we demonstrated that the method can estimate both resistivity model and distortion tensors, and that the method could be expected to enhance the reliability of the resistivity model estimated by the MT inversion.