Method for enhancing resistive anomalies in electromagnetic geophysical
survey data. Scaled values of a measured electromagnetic field parameter
are plotted on a depth section at locations related to corresponding
source/receiver locations. Scaling is performed relative to a reference
signal selected to represent a baseline free of unknown resistive bodies.
Scaled values are represented by a color scale in the display, and the
color scale may be adjusted to enhance perceived anomalies. The method
may be employed in either the frequency domain or the time domain.