Abstract:
Measurements of space-time distributions of the background emissions in the frequency range 0.5-5 Hz and their seasonal and diurnal variations are presented. The analysis of impedance ratio determines the presence of high space harmonics in the emission spectral distribution. The absence of this emission during the winter time correlates with the absence of any precursors before local earthquakes with M ~ 6. It is shown that the knowledge of the background emission behavior and its origin are very important for precursor phenomena monitoring.
