HR: 0800h
AN: GP41D-02    [Abstracts]
TI: Investigation of geomagnetic disturbances (F=1-5 Hz) before strong EQs in Kamchatka region
AU: * Kopytenko, Y
EM: galina@gh5667.spb.edu
AF: SPbF IZMIRAN, St.-Petersburg, Russia,
AU: Ismaguilov, V
EM: galina@gh5667.spb.edu
AF: SPbF IZMIRAN, St.-Petersburg, Russia,
AU: Schekotov, A
EM: checkit@ifz.ru
AF: IZMIRAN, Moscow, Russia,
AU: Molchanov, O
EM: oleg@molchanov.org
AF: IEP, Moscow, Russia,
AU: Hayakawa, M
EM: hayakawa@whistler.ee.uec.ac.jp
AF: UEC, Chofu, Japan,
AB: Regular observations of ULF electromagnetic disturbances at st. Karymshino in seismic active zone of Kamchatka peninsula were carried out by induction three-component high-sensitive magnetometer during 2001- 2003 years. Five seismic active periods with strong earthquakes (M>5) were displayed during this period. These EQs occurred at the Pacific at 20-60 km depth at 100-140 km distances to the East from the st. Karymshino. Analysis of normalized dynamic power spectra of data of high-sensitive (0.2 pT/sqrt(Hz)) three- component induction magnetometer achieved a significant disorder of daily variation and increasing of the magnetic disturbance intensities (from 0.2 to ~ 1 pT) in the whole investigated frequency range (1 - 5 Hz). The anomaly intensity increasing was observed during the 12-18 hours before main seismic shocks. Maximum of the increasing occurred during 4-6 hours before the EQs. A sharp decreasing of the magnetic disturbance intensities was observed 2-4 hours before the EQs. We suppose that physical processes in a hearth of forthcoming EQ lead to an irreversible avalanche-like formation of cracks and stimulation of the ULF electromagnetic disturbances.
DE: 0468 Natural hazards
DE: 1517 Magnetic anomalies: modeling and interpretation
DE: 3255 Spectral analysis (3205, 3280)
DE: 5109 Magnetic and electrical properties (0925)
DE: 6914 Electromagnetic noise and interference
SC: Geomagnetism and Paleomagnetism [GP]
MN: 2007 Joint Assembly