Are seismic velocities and electrical conductivities reconcilable?

Electromagnetic and seismic data are routinely used to create images of the earth's subsurface, but the resulting models are only rarely compared. That is because electrical conductivity and seismic velocity are two fundamentally different physical parameters that do not necessarily change coherently. In some cases though the comparison of resistivity and velocity models reveals striking similarities that suggest that the two parameters are at least structurally related. We use a newly developed joint inversion approach using a genetic algorithm that can help quantifying whether electrical conductivities and seismic velocities are influenced by the same structures. We apply the approach to various sites from the Canadian SNORCLE and Irish ISLE-MT datasets where collocated magnetotelluric and teleseismic measurements facilitate a comparison.