ИСТИНА

Activation of lithosphere geodynamic processes accompanying the preparation of earthquakes is associated with the movement of fluids in the geological environment. This leads to a change in electrical conductivity, dielectric and magnetic permeability and causes a change in the local magnetic response of the medium to global variations of the geomagnetic field. As a result, the magnetic field in the medium is the sum of external and local fields caused by bound charges and currents. Thus, the activation of various geodynamic processes is reflected in the intensity of the magnetic field. The dynamics of these local contributions to the magnetic field can be estimated by comparing the amplitudes of the same global magnetic variations recorded at different pairs of spaced stations. The first results of applying this technique were obtained by analyzing the data of a network of geomagnetic stations in Armenia. In the works of Skovorodkin Yu.P. and Grigoryan A.G., a connection between the variations of the local magnetic response of the medium and the preparation of the catastrophic Spitak earthquake (1988) was shown. Currently, due to the development of the instrument base and the existence of a vast archive of geomagnetic data, for example, Intermagnet, it becomes possible to comprehensively study the observed effect. Software implementation of the algorithms of the method of searching for variations of the local magnetic response made it possible to construct time series of these variations for different pairs of European geomagnetic stations. The work revealed anomalies of variations preceding the earthquake of magnitude 6.3, which occurred on April 6, 2009 near the station AQU located in Central Italy. This work was carried out with the financial support of the grant of the President of the Russian Federation for the support of scientific schools No. SS 5545.2018.5.