Magnetotelluric measurements in southern Alberta

Results are presented of magnetotelluric measurements at three locations in southern Alberta. At two stations interpretations using Cagniard's theory are consistent with other measurements which show a conductivity discontinuity near 80 km. However, at the station closest to the Rocky Mountains, the conductivity increase appears at approximately 35 km. In this case, it is unlikely that the long period decrease in the apparent resistivity curves is due to source effects.