Example 2, true models showing the full-extent inversion grids and the data geometry. (a) Resistivity model and MT data locations. (b) Velocity model: section through |$y=20$| km and the |$\pm 0.4$| km s⁻¹ velocity anomalies; seismic sources (green dots) and receivers. (c) Density model and gravity data locations. The regularization-coupling grid is identical to the FATT grid.