Changes in the geomagnetic field and magnetic tipper in the Baikal rift zone
Category: 14-3
UDC 550.832
Y.F. Moroz(1,2), G.I. Tatkov(2), T.A. Моrоz(1), Z.A. Tubanov(2), P.А. Predein(2)
1 Institute of Volcanology and Seismology FEB RAS, Petropavlovsk-Kamchatsky, Russia
2 Geological Institute SB RAS, Ulan-Ude, Russia
Abstract
The paper considers results of the study of secular variations of geomagnetic field from 1968 through 2011 and frequency curves of magnetic tipper and its time series for the last 10 years. It was revealed that average annual values of the geomagnetic field changed from 2003 through 2011. It is presumably associated with the increase of geodynamic processes in the southern part of the Baikal Rift related to the large Kultuck earthquake of 27.08.2008 г. (М=6.3).
Frequency parameters of magnetic tippers are attributed to the electro-conductivity of geological environment. It was shown that the tippers contain information about conductive zones of the rift. The behavior of magnetic tippers at 150–300 sec revealed an anomalous effect related to the Kultuck earthquake. The annual periodicity of magnetic tipper was observed at 1000–3000 sec. The possible origin of observed features in the behavior of the geomagnetic field and magnetic tippers is considered.
Keywords: geomagnetic field, field variations, magnetic tipper, electroconductivity, earthquakes.
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