Skip to main content

Advertisement

Co-seismic EM signals in magnetotelluric measurement—a case study during Bhuj earthquake (26th January 2001), India

Article metrics

  • 1032 Accesses

  • 12 Citations

Abstract

Significant changes in amplitude and frequency characteristics were observed in the magnetotelluric (MT) time series recorded during Bhuj earthquake (7.6 Mw), at a site 350 km from the epicenter. The telluric and magnetic signals recorded in the frequency range (10−1-101 Hz) of MT spectrum show considerable variations in their spectral characteristics during the earthquake event compared to the data recorded before and after the earthquake. The spectral analysis brings out sharp changes in amplitude of low-frequency signals during the earthquake as compared to the typical flat spectrum observed before and after the earthquake. The wavelet analysis of the electric and magnetic field data reveals two different spectral regimes; (1) the flat spectrum related to the natural MT signals, and (2) localized, high amplitude signals (in time and frequency) related to the onset of main shock. Three more high amplitude events are noted in the wavelet spectrum, after the main shock event, and can be speculated to be associated with the after-shock events. The MT impedance estimates clearly show scattered apparent resistivity and phase values during the earthquake suggesting that the high amplitude electric and magnetic signals were not related by an MT transfer function. The MT impedance estimates made before and after the earthquake are strikingly normal and smooth. The Pearson’s correlation coefficients between the orthogonal electric and magnetic fields show a drastic drop for the data measured during earthquake, while the MT fields recorded before and after the earthquake are well correlated. The observed MT signals during the seismic activity do not show any external geomagnetic origin and may be attributed to co-seismic EM phenomena. The probable mechanisms responsible for the co-seismic EM phenomena could be electro-kinetic and seismic dynamo effects.

References

  1. Biswas, S. K., Regional tectonic framework, structure and evolution of the western marginal basins of India, Tectonophysics, 135, 307–327, 1987.

  2. Cohen, A. and J. Kovacevic, Wavelets: the mathematical background, Proc. IEEE, 84(4), 1996.

  3. Egbert, G. and J. R. Booker, Robust estimation of geomagnetic transfer functions, Geophys. J. Int., 87, 173–194, 1986.

  4. Enomoto, Y., H. Hashimoto, N. Shirai, Y. Murakami, T. Mogi, M. Takada, and M. Kasahara, Anomalous geoelectric signals possibly related to the 200 Mt. Usu eruption and 2003 Tokachi-Oki earthquakes, Phys. Chem. Earth, 31, 319–324, 2006.

  5. Fenoglio, M. A., M. J. S. Johnston, and J. Byerlee, Magnetic and electric fields associated with changes in high pore pressure in fault zones—Application to the Loma Prieta ULF emissions, J. Geophys. Res., 100, 12951–12958, 1995.

  6. Fujinawa, Y., K. Takahashi, T. Matsumoto, H. Iitala, T. Doi, T. Nakayama, T. Sawada, and H. Sakai, Electric field variations related to seismic swarms, Bull. Earthq. Res. Inst. Univ. Tokyo, 76, 391–415, 2001.

  7. Gokarn, S. G., C. K. Rao, G. Gupta, B. P. Singh, and M. Yamashita, Deep crustal structure in central India using magnetotelluric studies, Geophys. J. Int., 144, 685–694, 2001.

  8. GSI, Seismotectonic atlas of India and its environs, Geological Survey of India, 2000.

  9. Guglielmi, A., A. Potapov, and B. Tsegmed, One mechanism for generation of the co-seismic electromagnetic oscillations, Phys. Chem. Earth, 29, 453–457, 2004.

  10. Harinarayana and others, Exploration of sub-trappean Mesozoic basins in the western part of Narmada-Tapti region of Deccan Syneclise, NGRI Tech. Report (unpublished), National Geophys. Res. Inst., Hyderabad, India, No: NGRI-2003-EXP-404, 2004.

  11. Hattori, K., A. Serita, C. Yoshino, M. Hayakawa, and N. Isezaki, Singular spectral analysis and principal component analysis for signal discrimination of ULF geomagnetic data associated with 2000 Izu Island Earthquake Swarm, Phys. Chem. Earth, 31, 281–291, 2006.

  12. Hayakawa, M., R. Kawate, O. A. Molchanov, and K. Yumoto, Results of ultra-low-frequency magnetic field measurements during the Guam earthquake of 8 August 1993, Geophys. Res. Lett., 23, 241–244, 1996.

  13. Honkura, Y., A. M. Isikira, N. Oshiman, A. Ito, B. Ucer, S. Baris, M. K. Tuncer, M. Matsushima, R. Pektas, C. Celik, 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.

  14. Honkura, Y., M. Matsushima, N. Oshiman, M. K. Tuncer, S. Baris, A. Ito, Y. Iio, and A. M. Isikara, Small electric and magnetic signals observed before the arrival of seismic wave, Earth Planets Space, 54, e9–e12, 2002.

  15. Honkura, Y., H. Satoh, and N. Ujihara, Seismo dynamo effects associated with the M7.1 earthquake of 26 May 2003 off Miyagi Prefecture and the M6.4 earthquake of 26 July 2003 in northern Miyagi Prefecture, NE Japan, Earth Planets Space, 56, 109–114, 2004.

  16. Johnston, M. J. S., Review of electric and magnetic fields accompanying seismic and volcanic activity, Surv. Geophys., 18, 441–475, 1997.

  17. Karakelian, D., S. L. Klemperer, A. C. Fraser-Smith, and G. A. Thompson, Ultra-low frequency electromagnetic measurements associated with the 1998 Mw 5.1 San Juan Bautista, California earthquake and implications for mechanisms of electromagnetic earthquake precursors, Tectonophysics, 359, 65–79, 2002.

  18. Kumar, P. and E. Foufoula-Georgiou, Wavelet Applications in Geophysics: A Review, Rev. Geophys., 35, 385–412, 1997.

  19. Lin, Y., Q. Li, M. Hayakawa, and X. Zeng, Wavelet analysis and seismo-magnetic effect, in Seismo Electromagnetics: Lithosphere Atmosphere Ionosphere Coupling, edited by Hayakawa and Molchanov, 61–68, TERRAPUB, Tokyo, 2002.

  20. Marquardt, D. W., An algorithm for least-square estimation of non-linear parameters, J. SIMA, 11, 431–441, 1963.

  21. Matsushima, M. and others, Seismoelectromagnetic Effect Associated with the Izmit Earthquake, Bull. Seismol. Soc. Am., 92, 350–360, 2002.

  22. Mishra, O. P. and D. Zhao, Crack density, saturation rate and porosity at the 2001 Bhuj, India, earthquake hypocenter: a fluid-driven earthquake?, Earth Planet. Sci. Lett., 212, 393–405, 2003.

  23. 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 Simatra, Indonesia,—Co-seismic change, Earth Planets Space, 52, 245–252, 2000.

  24. Molyneux, J. B. and D. R. Schmitt, First-break timing: arrival onset times by direct correlation, Geophysics, 64, 1492–1501, 1999.

  25. Nagao, T., Y. Orihara, T. Yamaguchi, I. Takahashi, K. Hattori, Y. Noda, K. Sayanagi, and S. Uyeda, Co-seismic geoelectric potential change observed in Japan, Geophys. Res. Lett., 27(10), 1535–1538, 2000.

  26. Nagao, T., Y. Enomoto, Y. Fujinawa, M. Hata, M. Hayakawa, Q. Huang, J. Izutsu, Y. Kushida, K. Maeda, K. Oike, S. Uyeda, and T. Yoshino, Electromagnetic anomalies associated with 1995 Kobe earthquake, J. Geodyn., 33, 401–411, 2002.

  27. Negi, A. S., S. K. Sahu, P. D. Thomas, D. S. A. N. Raju, R. Chand, and J. Ram, Fusing geologic knowledge and seismic in searching for subtle hydrocarbon traps in India’s Cambay Basin, The Leading Edge, 25, 872–880, 2006.

  28. Ogawa, T. and H. Utada, Electromgnetic signals related to incidence of a teleseismic body wave into a subsurface piezoelectric body, Earth Planets Space, 52, 252–260, 2000.

  29. Patro, B. P. K., T. Harinarayana, R. S. Sastry, M. Rao, C. Manoj, K. Naganjaneyulu, and S. V. S. Sarma, Electrical imaging of Narmada-Son Lineament Zone, Central India from magnetotellurics, Phys. Earth Planet. Inter., 148, 215–232, 2005.

  30. Ranganayaki, R. P., An interpretive analysis of magnetotelluric data, Geophysics, 49, 1730–1748, 1984.

  31. Sastry, R. S., N. Nandini, and S. V. S. Sarma, Electrical imaging of deep crustal features of Kutch, India, Geophys. J. Int., 172, 934–944, 2008.

  32. Simpson, F. and K. Bahr, Practical Magnetotellurics, Cambridge University Press, 2005.

  33. Singh, V., B. Singh, M. Kumar, and M. Haykawa, Identification of earthquake sources responsible for subsurface VLF electric field emissions observed at Agra, Phys. Chem. Earth, 31, 325–335, 2006.

  34. Ujihara, N., Y. Honkura, and Y. Ogawa, Electric and magnetic field variations arising from the seismic dynamo effect for aftershocks of the M7.1 earthquake of 26 May 2003 off Miyagi Prefecture, NE Japan, Earth Planets Space, 56, 115–123, 2004.

  35. Widarto, D., T. Mogi, Y. Tanaka, T. Nagao, K. Hattori, and S. Uyeda, Co-seismic geoelectrical potential changes associated with the June 4, 2000’s earthquake (Mw 7.9) in Bengkulu, Indonesia, Phys. Chem. Earth, 34, 373–379, 2009.

  36. Zlotnicki, J. and J. Le Mouel, Possible electrokinetic origin of large magnetic variations at la Fournaise volcano, Nature, 343, 633–636, 1990.

  37. Zlotnicki, J., V. Kossobokov, and J. Le Mouel, Frequency spectral properties of an ULF electromagnetic signal around the 21 July 1995, M=5.7, Yong Deng (China) earthquake, Tectonophysics, 334, 259–270, 2001.

  38. Zlotnicki, J., J. L. Le Mouel, R. Kanwar, P. Yvetot, G. Vargemezis, P. Menny, and F. Fauquet, Ground-based electromagnetic studies combined with remote sensing based on Demeter mission: A way to monitor active faults and volcanoes, Planet. Space Sci., 54, 541–557, 2006.

Download references

Author information

Correspondence to K. K. Abdul Azeez.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Azeez, K.K.A., Manoj, C., Veeraswamy, K. et al. Co-seismic EM signals in magnetotelluric measurement—a case study during Bhuj earthquake (26th January 2001), India. Earth Planet Sp 61, 973–981 (2009) doi:10.1186/BF03352947

Download citation

Key words

  • Co-seismic
  • electromagnetic
  • earthquake
  • Bhuj