Observation of precursors of large seismic events according to monitoring of the electric field of the surface layer of the atmosphere

Abstract

The work is based on 40 years of research by the authors of the project of electromagnetic fields of the infra-low-frequency range (ILF) and meteorological data at the physical experimental range of VlSU. The creation of a system for monitoring the electric and geomagnetic fields of the surface layer of the atmosphere in a network of stations spaced apart in space with a reliable assessment of the impact of global geophysical processes opens on this basis the possibility of predicting natural and man-made processes, analyzing seismic activity and the relationship of atmospheric electricity with the dynamics of meteorological processes. Long-term observations of electric and geomagnetic fields in the HF range have convinced the authors of the unique properties of EMPZ, bearing signs of many geophysical processes, including the processes of preparation of large seismic events. The catalogs of detected types of precursor anomalies in the electric field of the surface layer of the atmosphere are presented. Observed mainly anomaly types: seismogravitational oscillations; a sharp decrease in the field level up to a change in its sign; an increase in the level of the electric field. These anomalies (precursors) are observed both a few hours before the onset of an earthquake and a day, and seismic gravity fluctuations persist even after the moment of the earthquake. The developed catalogs of the precursors of strong earthquakes make it possible to analyze the pattern of changes in the character of the electric field in the surface layer of the atmosphere during the periods of preparation of seismic events.