Summary

We present a Contrast Source Inversion (CSI) method for marine Controlled Source Electromagnetic (mCSEM) data in conductive media. The inversion is carried out with respect to electric conductivity in a medium which is transversely isotropic in the vertical direction (TIV). The method is demonstrated on field data which, in this case, shows that the TIV inversion is preferred over isotropic inversion in order to identify weak anomalies. The reason for this is that both the horizontal and vertical conductivity affects the signal propagation in the overburden, while the response from the main reservoir is dominated by the vertical conductivity alone