Features of Electromagnetic Field of a Horizontal Electric Dipole Used in the Controlled Source RMT Method

The wave zone for a horizontal electric dipole (HED) as a source in the controlled source radiomagnetotelluric (CSRMT) method at the use of high frequencies (hundreds kilohertz) is allocated. The following features of the wave zone compare to the quasi-static one are noted: slower EM field attenuation with distance, changes of position of a favorable area for the CSRMT survey, changes of the directional diagram with the maximum of radiation in axial area, appearance of the polarization ellipticity of EM field components and delaying of ellipses big semi-axes relatively the linear polarization for quasi-static case. Existing of the polarization ellipticity for HED gives us a possibility to realize the tensor CSRMT survey with a single source of EM field only. Described features of the EM field in the wave zone of HED were confirmed by field experiments.