Geophysical Observatory in Kamchatka region for monitoring of phenomena connected with seismic activity

Abstract

Abstract. Regular monitoring of some geophysical parameters in association with seismicity has been carried out since last year at the Japan-Russian Complex Geophysical Observatory in the Kamchatka region. This observatory was organized in connection with the ISTC project in Russia and was motivated by the results of the FRONTIER/RIKEN and FRONTIER/NASDA research projects in Japan. The main purpose of the observations is to investigate the electromagnetic and acoustic phenomena induced by the lithosphere processes (especially by seismic activity). The seismicity of the Kamchatka area is analyzed and a description of the observatory equipment is presented. At present, the activity of the observatory includes the seismic (frequency range F = 0.5 − 40 Hz) and meteorological recordings, together with seismo-acoustic ( F = 30 − 1000 Hz) and electromagnetic observations: three-component magnetic ULF variations ( F = 0.003−30 Hz), three-component electric potential variations ( F ≤ 1.0 Hz), and VLF transmitter's signal perturbations ( F ∼ 10 − 40 kHz).

The Ionospheric Precursor to the 2011 March 11 Earthquake Based upon Observations Obtained from the Japan-Pacific Subionospheric VLF/LF Network

“…2 in collaboration with Russian colleagues (Uyeda et al 2002;Molchanov and Hayakawa 2008) and another station in Taiwan (Hayakawa et al 2010c). Observations at PTK have been performed regularly resulting in significant scientific output (Rozhnoi et al 2004(Rozhnoi et al , 2007(Rozhnoi et al , 2012a.…”

Study of electromagnetic emissions associated with seismic activity in Kamchatka region

“…In the paper by Uyeda et al (2001) the map of radio transmitters (in Japan, Australia, China and Hawaii) and receiver locations together with the areas of the supposed sensitivity for each wave path, are shown.…”

“…Apparently, the plausibility of this method could be high if the magnitude of the earthquakes is greater than 5.5-5.8 (Mulargia and Gasperini, 1992;Kawase et al, 1993;Hamada, 1993;Uyeda et al, 2000). According to Uyeda et al (2001) the equipment is measuring the potential differences V 2 , V 3 , V 4 from NS dipoles of different length l 2 = 80 m, l 3 = 230 m, l 4 = 470 m and potential differences V 5 , V 6 , V 7 from EW dipoles of the same length l 5 = 80 m, l 6 = 230 m, l 7 = 470 m. All potential differences V i (i = 2, 3, . .…”

“…Considering the peculiarities of the Kamchatka seismic activity (Uyeda et al, 2001) and the experimental data related to ULF/ELF precursors, a basic and rather difficult problem of the search for EQ precursor is their distinction from the natural background. The favourable factor for detection of the EQ precursor is related to the presence of very weak industrial noise.…”

“…the change in the ULF/ELF magnetic field, telluric currents, VLF signals from navigation radio transmitters) and acoustic emission. The measuring devices and digital registration systems placed at this observatory, as well as the seismic activity of the Kamchatka region, are described by Uyeda et al (2001).…”