A two-step three dimensional marine magnetotelluric inversion method with considering rugged seafloor topography: Synthetic studies

Inversion of magnetotelluric (MT) responses has been used to explore the electrical conductivity distribution Earth’s interior. In three-dimensional (3-D) inversions, it is significant use a good initial model, because final model obtained by most 3-D inversion methods influenced model. Although uniform models are widely in one-dimensional (1-D) alternatives, which could more appropriately represent actual variations This study presents two-step method, especially for marine cases. method first concentrates on obtaining 1-D and then inverts structures with it, both topography carefully taken into consideration. was tested synthetic different (depression-shaped, smoothly varying, channel-shaped square-shaped plateau topography) heterogeneous layers checkerboard-type anomalies (sharp or smooth lateral variations) embedded depth-dependent conductivity. The comparisons were done about an proposed that inverted from corrected responses. results inversions using this also compared models. Results tests discussed directional information newly introduced model-vector parameters. performance validity verified. It revealed some parameters be show convergence help select inverse