Also, computer visualization techniques have developed dramatically. 3D visualization and movie-making capabilities are routinely available today. Such techniques allow much more intuitive understanding of various dynamic physical processes. The example you are about to see is a transient magnetic field propagating inside the 3D Earth conductivity structure. Field was calculated using TEM3DL finite-difference forward modeling code developed in CEMI by T.Wang.
Solid lines show the host and the target.
Dashed line shows the borehole. Field amplitudes are normalized, red color corresponds to maximum, blue color corresponds to the minimum. As you can see, the dynamic of the field is very different.