Resistance

Area surveys undertaken using electrical methods of investigation have been used since the 1940s. The "Twin-Probe" method has been developed for archaeological purposes and is routinely used in GSB surveys. The basis for this method involves the injection of a small electrical current through the earth and the measurement of the subtle sub-surface variations in resistance. The technique is particularly suited to the detection of buried buildings and structural remains, although it can be used to locate a variety of other features, including football pitches! As with gradiometer surveys, the interpretation of resistivity or resistance data can be used by archaeologists and developers to formulate their project designs.

Sites Suitable for Electrical Resistivity Survey
 Any rural or semi-urban site free of excessive surface contamination and where a good electrical contact can be made with the ground.

Targets Detected by Electrical Resistivity Survey

• Masonry and brick foundations

• Floors and cavities

• Buried megaliths

• Palaeochannels and geological changes