Rapid Two-Dimensional Inversion of COPROD2 Data

We have inverted the large COPROD2 magnetotelluric data set using a very fast two- dimensional algorithm. Simultaneous calculation of static shifts in the data agrees well with those independently estimated using geological information. After correcting the data for static shifts, we find that the North American Central Plains conductivity anomaly consists of three compact, highly conducting strands running north-south in a resistive basement. These structures deepen to the west but internally they may dip to the east

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