- Copyright © 2006 Society of Exploration Geophysicists
“Bad news. The Earth is a conductor,” a distinguished geophysicist once told us, “and you can't propagate electromagnetic waves far into a conductor.” He is absolutely right. If you hope to use electromagnetic (EM) methods to image the subsurface at a resolution and a depth of penetration that match what is achievable via seismic methods, you are setting yourself up for disappointment. So, why bother? With such an impressive toolbox that includes seismic, gravity, magnetics, and a variety of other remote-sensing techniques for making inferences about the subsurface structure as well as a variety of other rock and fluid properties at a wide spectrum of scales, costs, and speeds, why introduce a new modality into the toolbox of geophysics?