Possible Generation of Quasi-Periodic Magnetic Precursors of Earthquakes

Resumo

A mechanism for the generation of quasi-periodic magnetic precursors of earthquakes is proposed on the basis of air heating above an impending earthquake, the rise of heated “bubbles,” the generation of acoustic–gravity waves (AGWs), the modulation of AGWs of the ionospheric current jet, and the generation of quasi-periodic oscillations of the geomagnetic field. According to estimates, the amplitude of a magnetic precursor can vary from 0.1 to 1 nT in the range of oscillation periods of ~10–1000 s.