Two-dimensional magnetotelluric inversion

Summary. When complex structure is encountered in magnetotelluric surveys, interpretation by locally fitted layered models is of questionable validity. However, when the processed data show two-dimensional structure, numerical inversion schemes for two-dimensional models may be constructed as an aid to regional data interpretation. The twodimensional magnetotellurics inversion problem is here formulated in a way that may be applied to many problems. A resulting computer program is analysed carefully in terms of its cost relative to that of simpler layered modelling. As an example, the method is applied to some field data where the interpretive advantages of the program become evident.

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