What does ERT actually measure?

GE5736 Electrical Methods - a discussion of what is actually measured during a resistivity survey.

[@jeremymaurer9554]

ERT can be used to detect groundwater because saturated soil will have a lower resistivity than unsaturated. It is often possible to map out the water table using ERT, if your depth penetration is enough.

[@MicheloMutakai]

How can i use ERT to assess ground water system using transects