Skip to main content

Small electric and magnetic signals observed before the arrival of seismic wave


Electric and magnetic data were obtained above the focal area in association with the 1999 Izmit, Turkey earthquake. The acquired data are extremely important for studies of electromagnetic phenomena associated with earthquakes, which have attracted much attention even without clear physical understanding of their characteristics. We have already reported that large electric and magnetic variations observed during the earthquake were simply due to seismic waves through the mechanism of seismic dynamo effect, because they appeared neither before nor simultaneously with the origin time of the earthquake but a few seconds later, with the arrival of seismic wave. In this letter we show the result of our further analyses. Our detailed examination of the electric and magnetic data disclosed small signals appearing less than one second before the large signals associated with the seismic waves. It is not yet solved whether this observational fact is simply one aspect of the seismic dynamo effect or requires a new mechanism.


  • Davis, P. M., D. D. Jackson, C. A. Searls, and R. L. McPherron, Detection of tectonomagnetic events using multichannel predictive filtering, J. Geophys. Res., 86, 1731–1737, 1981.

    Article  Google Scholar 

  • Gershenzon, N. I., M. B. Gokhberg, and S. L. Yunga, On the electromagnetic field of an earthquake focus, Phys. Earth Planet. Inter., 77, 13–19, 1993.

    Article  Google Scholar 

  • Haartsen, M. W. and S. R. Pride, Electroseismic waves from point sources in layered media, J. Geophys. Res., 102, 24745–24769, 1997.

    Article  Google Scholar 

  • Honkura, Y, Electric and magnetic approach to earthquake prediction, in Current Research in Earthquake Prediction I, Edited by T. Rikitake, pp. 301–383, Center Academic Publications Japan/ D. Reidel Publishing Company, 1981.

  • Honkura, Y., and Y. Kuwata, Estimation of electric fields in the conducting Earth’s crust for oscillating electric current dipole sources and implications for anomalous electric fields associated with earthquakes, Tectonophysics, 224, 257–263, 1993.

    Article  Google Scholar 

  • Honkura, Y, A. M. Isikara, N. Oshiman, A. Ito, B. Üçer, Ş. Baris, M. K. Tunçer, M. Matsushima, R. Pektas, C. Çelik, S. B. Tank, F. Takahashi, M. Nakanishi, R. Yoshimura, Y. Ikeda, and T. Komut, Preliminary results of multidisciplinary observations before, during and after the Kocaeli (Izmit) earthquake in the western part of the North Anatolian Fault Zone, Earth Planets Space, 52, 293–298, 2000.

    Article  Google Scholar 

  • Iio, Y., Observations of the slow initial phase generated by microearthquakes: implications for earthquake nucleation and propagation, J. Geophys. Res., 100, 15333–15349, 1995.

    Article  Google Scholar 

  • Ishido, T. and H. Mizutani, Experimental and theoretical basis of electrokinetic phenomena in rock-water systems and its application to geophysics, J. Geophys. Res., 86, 1763–1775, 1981.

    Article  Google Scholar 

  • Iyemori, T., T. Kamei, Y. Tanaka, M. Takeda, T. Hashimoto, T. Araki, T. Okamoto, K. Watanabe, N. Sumitomo, and N. Oshiman, Co-seismic geomagnetic variations observed at the 1995 Hyogoken-nanbu earthquake, J. Geomag. Geoelectr, 48, 1059–1070, 1996.

    Article  Google Scholar 

  • Johnston, M. J. S. and A. T. Linde, Implications of crustal strain during conventional, slow, and silent earthquakes, in International Handbook of Earthquake and Engineering Seismology, 81A, pp. 589–605, 2002. a]Matsushima, M., Y. Honkura, N. Oshiman, S. Baris, M. K. Tunçer, S. B. Tank, C. Çerik, F. Takahashi, M. Nakanishi, R. Yoshimura, R. Pektas, T. Komut, E. Tolak, A. Ito, Y. Iio, and A. M. Isikara, Seimo-elecromagnetic effect associated with the Izmit earthquake and its aftershocks, Bull. Seismol. Soc. Am., 92, 350–360, 2002.

    Article  Google Scholar 

  • Mizutani, H., T. Ishido, T. Yokokura, and S. Ohnishi, Electrokinetic phenomena associated with earthquakes, Geophys. Res. Lett., 3, 365–368, 1976.

    Article  Google Scholar 

  • Mogi, T., Y. Tanaka, D. S. Widarto, E. M. Arsadi, N. T. Puspito, T. Nagao, W. Kanda, and S. Uyeda, Geoelectric potential difference monitoring in southern Sumatra, Indonesia —Co-seismic change—, Earth Planets Space, 52, 245–252, 2000.

    Article  Google Scholar 

  • Nagao, T., Y. Orihara, T. Yamaguchi, I. Takahashi, K. Hattori, Y. Noda, K. Sayanagi, and S. Uyeda, Co-seismic geoelectric potential changes observed in Japan, Geophys. Res. Lett., 27, 1535–1538, 2000.

    Article  Google Scholar 

  • Ozalaybey, S., M. Ergin, M. Aktar, C. Tapirdamaz, F. Biçmen, and A. Yörük, The 1999 Izmit earthquake sequence in Turkey: seismological and tectonic aspects, Bull. Seismol. Soc. Am., 92, 376–386, 2002.

    Article  Google Scholar 

  • Sasai, Y., Application of the elasticity theory of dislocation to tectonomagnetic modeling, Bull. Earthq. Res. Inst., 55, 387–447, 1980.

    Google Scholar 

  • Stacey, F. D. and M. J. S. Johnston, Theory of the piezo-magnetic effect in titanomagentite-bearing rocks, Pure Appl. Geophys., 97, 146–155, 1972.

    Article  Google Scholar 

  • Yamada, I. and H. Murakami, Self-potential variations associated with quarry blasts, Zisin, 35, 393–400, 1982 (in Japanese with English abstract).

    Google Scholar 

Download references

Author information

Authors and Affiliations


Corresponding author

Correspondence to Y. Honkura.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Honkura, Y., Matsushima, M., Oshiman, N. et al. Small electric and magnetic signals observed before the arrival of seismic wave. Earth Planet Sp 54, e9–e12 (2002).

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

Key words