Characteristics of flux-time profiles, temporal evolution, and spatial distribution of radiation-belt electron precipitation bursts in the upper ionosphere before great and giant earthquakes

Abstract

The analysis of energetic electron observations made by the DEMETER satellite reveals that radiation belt electron precipitation (RBEP) bursts are observed in general several (~1-6 days) before a large (M > 6.5) earthquake (EQ) in the presence of broad band (~1-20 kHz) VLF waves. The EBs show in general a relative peak-to-background flux increase usually < 100, they have a time duration of ~0.5 - 3 min, and their energy spectrum reach up to energies