On magnetic precursors of earthquakes

A simple classification is proposed for magnetic precursors of earthquakes. The high-latitude observations of the so-called Big Magnetic Pulses (BMP)—isolated high-amplitude magnetic pulses that sporadically arise against the undisturbed magnetic background—are used for searching for a probable correlation between BMPs and earthquakes. It is shown by the superposed epoch analysis that seismic activity slightly increases after BMPs. A wide maximum in the number of the earthquakes is observed within the first hour after the BMP. Thus, probably, a new type of magnetic precursors has been found. However, the mechanism of the relationship between BMPs and earthquakes remains open to discussion.