Through the principle of electromagnetic induction, the device used during the survey induces so called eddy currents in the uppermost part of the soil, which are measured to estimate the electric conductivity of the subsurface. The measurements are instantaneous and require no direct contact between the ground and the device, allowing for highly efficient surveying, whether in hand-held or trailer-mounted configuration.

The depth of exploration using this method depends on the device type selected prior to the surveying as well as on the measuring configuration. The location of the surveying is positioned by GPS in all cases, which helps to place the results into a reference coordinate system. The conductivity profiles and maps obtained from the processing of the data are suitable for detecting and mapping subsurface objects having contrasting conductivities compared to their surroundings. These are for example wall remnants, pipelines, cavities, which is why we often use this surveying method for archeological and geotechnical works. In addition, the method is suitable for delineating different near-surface geological and soil formations, making it ideal for differentiating soil types, determining their soil parameters, or for other agro-geophysical exploration.