The TDEM (TEM) methods are based on the investigation of transients processes induced in the Earth as the result of “step-like” change of the current amplitude in non-grounded loop or grounded power dipole. The depth of investigation in TDEM is regulated by the moment of the power dipole and duration of the recording. Therefore, measured field carries information about the variation of the electrical properties of the rocks depending on the depth. The method can be used with a high level of artificial noise and the maximum depth of investigation with TDEM does not exceed 5-10 km. TDEM method is mainly used for mining exploration, structural tasks, as well as oil and gas exploration.