The determination of anomalous zone according to the rate of induction of permanent magnetic fields

A real magnetic field observed on the Earth's surface reflects the total effect of the action of different sources. The main contribution to the geomagnetic field is given by the field of eccentric dipole and by its non – dipole constituents, the sources of which are located in the outer core of the Earth. To this main field one can add a field caused by the magnetization of rocks of the crust which is summed np with a magnetic field of extra – terrestrial origin. So a full vector of a magnetic field is formed.