Reference field for the airborne magnetic data

A comparison of satellite and surface surveys of geomagnetic anomalies is performed. A special regional aeromagnetic survey was carried out at the Urals. Different models of the reference field for the region under investigation were studied. A reference field has been constructed using polynomial of 4-th order. The long-wavelength component of the anomalous magnetic field was selected. It is shown that when dividing the magnetic field of the Earth into a main and anomalous parts by spherical harmonic analysis, a large part of the magnetic field from the crust is included within the main field model. A model of the crustal magnetization of the Northern Eurasia is constructed.