Electrical Resistivity Surveys

Electrical Resistivity is a kind of geophysical survey used to locate buried features by mapping differences in the way that subsurface materials conduct an electric current.

Using a resistivity meter a controlled electric current is passed through the subsurface. Designated electrodes carry the current while other electrodes measure the voltage passed through the ground; the resistivity is determined and recorded.

In general, fine, densely packed, damp, silty material offers little resistance to current passed through it, but stony deposits and those with abundant spaces in the matrix tend to be more resistant. Different arrays of electrodes allow different depths to be targeted, and by moving the electrodes in a systematic pattern a detailed profile of subsurface resistivity conditions can be established.

Electrical resistivity survey results