Variation of Altitude Observed on the Occasion of the Tohoku Earthquake (M = 9.0) Occurred on March 11, 2011

Abstract

Since October 1, 2010, a GPS receiver is put into operation at Tokai (Japan) in an experiment on Neutrino Physics (T2K). A significant variation of the altitude was detected from the beginning of March 2011, so that it has made worthwhile to investigate the possibility that such variations could be correlated to the Tohoku earthquake. In order to investigate in details this possibility, we analyzed the GPS data collected during 2011 by GEONet the GPS Earth Observation Network (GEONET). GEONET is the GPS network of Japan and consists of 1240 permanent stations. Preliminary results of the analysis seemed to show ten days before the earthquake, some possible anomalous behaviors of the stations. These anomalous behaviors were particularly relevant for stations of the network near the epicentral area. While co-seismic and post-seismic variations are widely expected, the anomalies recorded about ten days before the earthquake could be seriously considered among short-term precursors of the earthquake. In order to confirm this possibility, more detailed studies have been performed. In particular, GEONET currently makes available only daily solutions of the stations coordinates. On the contrary, it is very important to improve the time resolution just to understand the features of the anomalies till the last hours before the Earthquake. For this reason, we have performed an analysis to evaluate the coordinates and movement on hourly basis so improving the time resolution.

Share and Cite:

P. Milillo, T. Maggipinto and P. Francesco Biagi, "Variation of Altitude Observed on the Occasion of the Tohoku Earthquake (M = 9.0) Occurred on March 11, 2011," Open Journal of Earthquake Research, Vol. 3 No. 1, 2014, pp. 22-29. doi: 10.4236/ojer.2014.31004.

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1] O. A. Molchanov, et al., “Precursory Effects in the Sub- ionospheric VLF Signals for the Kobe Earthquake, Physics of the Earth and Planetary Interiors,” 1998.
[2] Hayakawa, et al., “On the Correlation between Ionospheric Perturbations as Detected by Subionospheric VLF/LF Signals and Earthquakes as Characterized by Seismic Intensity,” Journal of Atmospheric and Solar-Terrestrial Physics, Vol. 72, No. 13, 2010, pp. 982-987. http://dx.doi.org/10.1016/j.jastp.2010.05.009
[3] http://www.izmiran.ru/projects/IK19/
[4] Kasahara, et al., “The Ionospheric Perturbations Associated with Asian Earthquakes as Seen from the Subionospheric Propagation from NWC to Japanese Stations,” Natural Hazards and Earth System Sciences, Vol. 10, No. 8, 2010, pp. 581-588. http://dx.doi.org/10.5194/nhess-10-581-2010
[5] Hayakawa, et al., “A Statistical Study on the Correlation between Lower Ionospheric Perturbations as Seen by Su-bionospheric VLF/LF Propagation and Earthquakes,” Journal of Geophysical Research, Vol. 115, No. A9, Article ID: A09305.
[6] K. Heki, “Ionospheric Electron Enhancement Preceding the 2011 Tohoku-Oki Earthquake,” Geophysical Research Letters, Vol. 38, No. 8, Article ID: L17312.
[7] http://www.gsi.go.jp/
[8] http://acc.igs.org
[9] http://www.denshi.e.kaiyodai.ac.jp/ja/
[10] Bernese, “GPS Software Reference Manual,” University of Bern-Version 5.0, 2007.
[11] http://facility.unavco.org
[12] http://sopac.ucsd.edu/
[13] M. Hayakawa, et al., “A Possible Precursor to the 2011 3.11 Japan Earthquake: Ionospheric Perturbations as Seen by Subionospheric VLF/LF Propagation. (in Phase of Pubblication),” 2011.
[14] Biagi, et al., “Anomalies Observed in VLF and LF Radio Signals on the Occasion of the Western Turkey Earthquake (M = 5.7) at May 19, 2011 (in phase of pubblication),” 2011.

Copyright © 2024 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.