Alternatives in Electrical Prospecting with Controlled Sources
V.S. Mogilatov · Geophysics of the 21st Century - The Leap into the Future · 2003
Some advantages and problems of a new geoelectrical prospecting method are discussed here. This method is based on using a new source, the circular electric dipole (CED). The source is installed in the following way. One of the transmitter poles is grounded in the central point. The other pole is uniformly grounded around a radius determined by the depth of investigation desired. It can be defined as a noninductive source, generating a transverse magnetic (TM) non-stationary field. CED has no magnetic field of its own. It is a pure galvanic source, which differs from a loop (a pure inductive source) and from a line (cable), which is both galvanic and inductive. The normal magnetic field on the earth's surface is absent (within the quasi-static approximation). Taking into consideration the pronounced vertical character of the currents under the central electrode and current circulation in the vertical planes we propose to term the electrical prospecting technique using the CED as the ‘vertical electric current soundings method’ (VECS). At present, real measurements of the magnetic components with an attached CED-array are the most promising. The author consider results of the field tests.