Patent ID: 8886463

Claim:
A method of characterizing an earth subterranean structure using a measurement assembly including electromagnetic (EM) receivers and one or more EM sources, the method comprising: receiving at a data processor measured voltage data collected by the EM receivers in response to transmission by the one or more EM sources; generating, in the data processor, common receiver position gathers from the measured voltage data; interpolating and resampling, in the data processor, the measured voltages to a plurality of common source positions; computing, based on a model, predicted EM data; and iteratively performing inversion at the data processor according to a cost function that computes a difference between the interpolated, resampled measured voltage data and a product of a term containing the predicted EM data and a term containing a correction factor for distortion caused by a near-surface man-made structural heterogeneity, wherein iteratively performing the inversion solves for parameters of the model and the correction factor for distortion caused by the near-surface man-made structural heterogeneity.