JDR Vol.3 No.4 pp. 252-260
doi: 10.20965/jdr.2008.p0252


Real-Time Eruption Magnitude Estimation from Far-Field Geodetic Data: A Proposal for Volcanic Early Warning

Hiroaki Takahashi

Institute of Seismology and Volcanology, Graduate School of Science, Hokkaido University, N10, W8, Kita-ku, Sapporo, Hokkaido 060-0810, Japan

April 15, 2008
May 29, 2008
August 1, 2008
volcano eruption, eruption magnitude, volcanic early warning, disaster operation, real-time analysis
Recent developments in dense geodetic observation of volcanoes have enabled us to handle data in real-time. Monitoring agencies detect volcano unrest using numerous instruments and quickly broadcast volcanic activity alerts but based on little quantitative information. Residents on volcanoes seek predictive, practical, and reliable alerts including place, time, and magnitude directly linked to disaster mitigation activities. A strategy I proposed in this study answers the question of the magnitude of a foreseen eruption. Far-field displacements by geodetic instruments provide the signals of deflating magma reservoirs, and may give predictive maximum magnitude Mvp of a looming eruption. This may play an important role in antidisaster measures because it is the parameter most determinate for evacuation. Continuous monitoring of Mvp may also yield valuable information for judging the termination of an eruption because its stagnation indicates magma feeding disconnection from reservoir to shallower part. I believe that predictive volcanic early warnings with quantitative Mvp can provide truly effective, practical information to residents and local governments potentially affected by active volcanoes.
Cite this article as:
H. Takahashi, “Real-Time Eruption Magnitude Estimation from Far-Field Geodetic Data: A Proposal for Volcanic Early Warning,” J. Disaster Res., Vol.3 No.4, pp. 252-260, 2008.
Data files:
  1. [1] S. Tsukada, T. Odaka, K. Asiya, K. Ohtake, and D. Nozaka, “Analysis of the Envelope Waveform of the Initial Part of P-waves and its Application to Quickly Estimating the Epicentral Distance and Magnitude,” Zisin 2, Vol.56, pp. 351-361, 2004.
  2. [2] M. Matsumura, Y. Ito, H. Kimura, K. Obara, S. Sekiguchi, S. Hori, and K. Kasahara, “Development of Accurate and Quick Analysis System for Source Parameters (AQUA),” Zisin 2, Vol.59, pp. 167-184, 2006.
  3. [3] C. Newhall and S. Self, “The Volcanic Explosivity Index (VEI): an estimate of explosive magnitude for histrical volcanism,” J. Geophys. Res., Vol.87, pp. 1231-1238, 1982.
  4. [4] Y. Hayakawa, “A Proposal of Eruption Magnitude Scale,” Kazan, Vol.38, pp. 223-226, 1993.
  5. [5] K. Sezawa, “The Plastico-Elastic Deformation of a Semi-Finite Solid Body due to an Internal Force,” Bull. Earthq. Res. Inst., Vol.9, pp. 398-406, 1931.
  6. [6] K. Mogi, “Relation between the Eruptions of Various Volcanoes and the Deformations of the Ground Surfaces around them,” Bull. Earthq. Res. Ins., Vol.36, pp. 99-134, 1958.
  7. [7] N. Okazaki, H. Takahashi, M. Kasahara, S. Ishimaru, H. Y. Mori, S. Kitagawa, K. Fujiwara, and M. Churei, “Crustal deformation associated with the 2000 eruption of Usu volcano as observed by a dense GPS array,” Kazan, Vol.47, pp. 547-557, 2002.
  8. [8] M. Irwan, F. Kimata, and N. Fujii, “Time Dependent Modeling of Magma Intrusion During the Early Stage of the 2000 Miyakejima Activity,” J. Volcano. Geotherm. Res., Vol.150, pp. 202-212, 2006.
  9. [9] H. Ueda, E. Fujita, M. Ukawa, E. Yamamoto, M. Irwan, and F. Kimata, “Magma Intrusion and Discharge Process at the Initial Stage of the 2000 Activity of Miyakejima, Central Japan, Inferred from Tilt and GPS data,” Geophys. J. Int., Vol.161, pp. 891-906, 2005.
  10. [10] M. Murase, M. Irwan, S. Kariya, T. Tabei, T. Okuda, R. Miyajima, J. Oikawa, H. Watanabe, T. Kato, S. Nakao, M. Ukawa, E. Fujita, M. Okayama, F. Kimata, and N. Fujii, “Time Dependent Model of Magma Intrusion in and around Miyake and Kozu Islands, Central Japan in June-August 2000,” J. Volcano. Geotherm. Res., Vol.150, pp. 213-231, 2006.
  11. [11] Y. Okada, “Internal Deformation due to Shear and Tensile Faults in a Half-Space,” Bull. Seism. Soc. Am., Vol.82, pp. 1018-1040, 1992.
  12. [12] K. Yamashina, “Stress Fields and Volcanic Eruptions,” Kazan, Vol.30, pp. S101-S119, 1986.
  13. [13] Geological Survey of Japan, “Database of Japanese Active Volcanoes,”
  14. [14] Smithsonian Institution, “Global VolcanisMvprogram,”
  15. [15] J. Okada, “Dacitic Magma Doming Associated with Shallow Inflation and Deep Deflation Sources — An Application to Mt. Usu, Japan,” Geophys. Bull. Hokkaido Univ., Vol.69, pp. 191-206, 2006.
  16. [16] T. Nishimura, S. Ozawa, M. Murakami, T. Sagiya, T. Tada, M. Kaidzu, and M. Ukawa, “Crustal Deformation Caused by Magma Migration in the Northern Izu Islands, Japan,” Geophys. Res. Lett., Vol.28, pp. 3745-3748, 2001.
  17. [17] M. Ukawa, E. Fujita, E. Yamamoto, Y. Okada, and M. Kikuchi, “The 2000 Miyakejima Eruption: Crustal Deformation and Earthquakes Observed by the NIED Miyakejima Observation Network,” Earth Planets Space, Vol.52, pp. xix-xxvi, 2000.
  18. [18] E. Rivalta and P. Segall, “Magma Compressibility and the Missing Source for Some Dike Intrusions,” Geophys. Res. Lett., Vol.35, L04306, doi:10.1029/2007GL032521, 2008.
  19. [19] Geographical Survey Institute,
  20. [20] Y. Okada, K. Kasahara, S. Hori, K. Obara, S. Sekiguchi, H. Fujiwara, and A. Yamamoto, “Recent Progress of Seismic Observation Networks in Japan — Hi-net, F-net, K-NET and KiK-net —,” Earth Planets Space, Vol.56, pp. xv-xxviii, 2004.
  21. [21] H. Takahashi, N. Okazaki, H. Ueda, and K. Obara, “An attempt of real-time magnitude estimation for volcanic eruption,” Programme and Abstracts of the Volcanological Society of Japan, pp. 82, 2006.
  22. [22] Japan Meteorological Agency, “Volcanic Warnings and Volcanic Alert Levels,”
  23. [23] T. Nishimura, “Ground Deformation due to Magma Ascent with and without Degassing,” Geophys. Res. Lett., Vol.33, L23309, doi:10.1029/2006GL028101, 2006.
  24. [24] S. Iwashita, H. Takahashi, N. Okazaki, J. Miyamura, M. Kasahara, M. Ichiyanagi, R. Takahashi, and M. Nakagawa, “Volcanic Inflation of Mount Hokkaido-Komagatake, Japan, Determined from a Dense GPS Array,” Geophys. Res. Lett., Vol.32, L20304, doi:10.1029/2005GL023438, 2005.
  25. [25] K. Ishihara, “Geophysical Evidences on the Existence of Magma Reservoir and Conduit at Sakurajima Volcano, Japan,” Ann. Disas. Prev. Res. Inst., Kyoto Univ., Vol.311B-1, pp. 59-73, 1988.

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