Interpretation of the magnetotelluric impedance tensor: regional induction and local telluric distortion

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K. Bahr


A method for the interpretation of the magnetotelluric (MT) impedance tensor, the telluric-vector technique, is presented. The phase information of all impedance tensor elements is used to distinguish between local telluric distortion and regional induction. A model incorporating a superposition of the effects of local surface anomalies and a regional 1-D, 2-D, or 3-D conductivity distribution is applied. In 2-D regional structures, a complete separation of the contributions of local and regional anomalies is possible if additional information from geomagnetic depth sounding (GOS) is used. A new skewness parameter derived from phases alone is introduced to measure the three-dimensionality of the regional structure independent of local distortions.

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Bahr, K. (1987). Interpretation of the magnetotelluric impedance tensor: regional induction and local telluric distortion. Journal of Geophysics, 62(1), 119-127. Retrieved from
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