Electromagnetic methods include a large array of techniques used for measuring natural or provoked electromagnetic fields, in time domain or frequency domain. The equipments are specialized for specific targets, starting from metal detectors and radars, for shallow depths investigations, to MT complex system, measuring conductivity variations for depths exceeding tens of kilometers.
There are some key parameters that rule the applicability of the EM method in particular situations. For example the radar method, recording the time travel and amplitude of the reflected wave, is influenced by electric and magnetic properties of terrain (dielectric constant, magnetic permeability, electric conductivity, EM wave velocity). Therefore, the performances of this method are limited to shallow targets, such as in civil engineering domain, and are not applicable to targets located at increased depths.
Usually, conductive terrains (massive ore bodies, underground water, polluted zones containing ionic solutions) are limiting obstacles that reduce the applicability of EM methods.
Geomathics One is very experienced in using these methods and various equipments to investigate deep structures bearing hydrocarbons resources or thermal water.