TDEM & FDEM Electromagnetic Investigations

Electromagnetic investigations, both in the time domain (TDEM) and in the frequency domain (FDEM), involve the generation of an artificial magnetic impulse (the primary field), which induces a secondary field within the land. Electromagnetic investigations in the time domain (TDEM) involve reconstructing true resistivity distribution in the subsoil. The FDEM investigation method (in the frequency dominion) enables the mapping of phase variation and secondary electromagnetic field amplitude values with respect to the induced primary field. This type of investigation is carried out above all to identify buried metal objects, in archaeological research, investigations in waste disposal plants, the identification of cavities and buried debris, environmental investigations and the identification of underground ducts in non-urbanised areas.