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Deep seismic activities preceding the three large ‘shallow’ earthquakes off south-east Hokkaido, Japan—the 2003 Tokachi-oki earthquake, the 1993 Kushiro-oki earthquake and the 1952 Tokachi-oki earthquake

Abstract

The 2003 Tokachi-oki earthquake of M 8.0, which occurred off the south-east coast of Hokkaido, Japan, was preceded by noticeable deep seismicity in the subducting slab, including a deep-focus earthquake of M 7.1. The 1952 Tokachi-oki earthquake of M 8.2 and the 1993 Kushiro-oki earthquake of M 7.5, which occurred also off the south-east of Hokkaido along the Kurile Trench, were also preceded by high deep seismicity including large deep-focus earthquakes of the M 7 or over (focal depths 200–600 km). The relations between the deep seismicity and the ‘shallow’ large earthquake (focal depth ≤ 100 km) in these three cases are quite similar. This result strongly supports the author’s view (Mogi, 1973, 1988) that large ‘shallow’ earthquakes along the subduction zones are sometimes preceded by the occurrence of large deep-focus earthquakes.

References

  1. Hokkaido University, 1993 Kushiro-oki earthquake (1), Rep. Coord. Comm. Earthq. Predict., 50, 17–22, 1993 (in Japanese).

    Google Scholar 

  2. Japan Meteorological Agency (JMA), The kushiro-oki earthquake, 1993 (January 15, M 7.8), Rep. Coord. Comm. Earthq. Predict., 50, 8–16, 1993 (in Japanese).

    Google Scholar 

  3. Kasahara, M., 1993 Kushiro-oki earthquake, in The Course of 30 years of the Coordinating Committee for Earthquake Prediction, 149–159, 2000 (in Japanese).

    Google Scholar 

  4. Mogi, K., Relationship between shallow and deep seismicity in the western Pacific region, Tectonophysics, 17, 1–22, 1973.

    Article  Google Scholar 

  5. Mogi, K., Earthquake Prediction, 355 pp. Academic Press, Tokyo, 1985.

    Google Scholar 

  6. Mogi, K., Downward migration of seismic activity prior to some great shallow earthquakes in Japanese subduction zone—A possible intermediate-term precursor, PAGEOF, 126, 447–463, 1988.

    Article  Google Scholar 

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Correspondence to Kiyoo Mogi.

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Mogi, K. Deep seismic activities preceding the three large ‘shallow’ earthquakes off south-east Hokkaido, Japan—the 2003 Tokachi-oki earthquake, the 1993 Kushiro-oki earthquake and the 1952 Tokachi-oki earthquake. Earth Planet Sp 56, 353–357 (2004). https://doi.org/10.1186/BF03353064

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Key words

  • Tokachi-oki
  • Kushiro-oki
  • deep-focus foreshocks
  • downward migration
  • subducting slab
  • trigger