4D self-potential tomographic techniques for hydrogeological purposes

In the last years the new electrical imaging techniques have been largely applied to support hydrogeological investigations, in particular the analysis of Self-Potential ground surface anomalous pattems has been revealed as a powerful tooI to study pollutant diffusion processes in aquifers, groundwater circulation systems in landslide body, seepage phenomena in dam embankment and in all other cases concerning fluid flows in the subsoil (Sharma, 1997 and references therein).