ULF electromagnetic variations connected with a seismic center
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Abstract
At present investigation of low-frequency radiation (ULF) of electromagnetic fields in a range of frequencies 10-0,001 Hz having lithosphere origin has an actual meaning as there is an assumption, that with their help it is possible to trace processes taking place in earthquake preparation. In works [1-5] ULF radiations before strong earthquakes (М4) and during time aftershock activity in different regions of globe were investigated by authors, therefore it was revealed, that before activation of tectonic processes the increase in amplitude ULF since several hours about several days before earthquake is observed. However ULF is possible to register in close epicenter zones in radius 120-150 km. The above-stated frequency range of electromagnetic radiations are a consequence of two processes - ULF from area of active tectonic movements of change of geoelectric conductivity inside and nearby the centre of earthquakes that leads to occurrence on a terrestrial surface of the electromagnetic waves reflected from lithosphere of anomaly [6-9].
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References
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