Results of Observations of Pulsed ULF Electromagnetic Signals Preceding Earthquakes Minutes Before the Shock
The study presents an overview of the results of long-term observations of pulsed ultra-low frequency (ULF) electromagnetic signals detected from remote earthquakes minutes before a seismic event. The signals were isolated from the data of long-term observations of UNF variations of the Earth's electromagnetic field at two geophysical observatories Borok and College separated by latitude and longitude. The precursors were observed in the frequency range from 0 to 5 Hz and differed in the type of dynamic spectrum from the known forms of pulsations of natural (non-seismic) origin. In the subsequent series of papers following the first publications, the research was continued. We examined the features of the manifestation of signals from earthquakes occurring in different regions of the globe at different magnitudes and depths of the hearth, daily and seasonal dependences of the number of their occurrence in observatories, repeatability in aftershocks and the nature of the spatial distribution of their generation zones on the Earth's surface. The proposed paper summarizes the main results of the works published to date in the study of the earthquake-anticipating ULF-electromagnetic signals.