The electrical resistivity method uses a series of electrodes nailed into the ground about six meters deep along a selected straight profile or 3D grid. The distance between the electrodes depends on the desired depth of investigation and the target being imaged.  The further apart the electrodes, the “deeper” the electricity goes into the earth, at the expense of resolution.  The most commonly used configurations activate four electrodes at a time, two for passing current into the ground and two for measuring the potential difference.

Soil Resistivity Surveys

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