pure and applied geophysics

, Volume 122, Issue 6, pp 765–780 | Cite as

Temporal variation of crustal deformation during the days preceding a thrust-type great earthquake — The 1944 Tonankai earthquake of magnitude 8.1, Japan

  • Kiyoo Mogi


The temporal variation in precursory ground tilt prior to the 1944 Tonankai (Japan) earthquake, which is a great thrust-type earthquake along the Nankai Trough, is discussed using the analysis of data from repeated surveys along short-distance leveling routes.Sato (1970) pointed out that an anomalous tilt occurred one day before the earthquake at Kakegawa near the northern end of the focal region of the earthquake. From the analysis of additional leveling data, Sato's result is re-examined and the temporal change in the ground tilt is deduced for the period of about ten days beginning six days before the earthquake. A remarkable precursory tilt started two or three days before the earthquake. The direction of the precursory tilt was up towards the south (uplift on the southern Nankai Trough side), but the coseismic tilt was up towards the southeast, perpendicular to the strike of the main thrust fault of the Tonankai earthquake. The postseismic tilt was probably opposite of the coseismic tilt. The preseismic tilt is attributed to precursory slip on part of the main fault. If similar precursory deformation occurs before a future earthquake expected to occur in the adjacent Tokai region, the deformation may help predict the time of the Tokai earthquake.

Key words

precursory ground tilt temporal variation of crustal deformation the 1944 Tonankai earthquake leveling survey earthquake prediction 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Ando, M. (1975),Possibility of a Major Earthquake in the Tokai District, Japan and its Pre-estimated Seismotectonic Effects, Tectonophysics25, 69–85.Google Scholar
  2. Fitch, T., andScholz, C. H. (1971),Mechanism of Underthrusting in Southwest Japan: A Model of Convergent Plate Interactions, J. Geophys. Res.76, 7260–7292.Google Scholar
  3. Imamura, A. (1945),Land Deformations Associated with the Recent Tōkaido Earthquake, Proc. Japan Academy21, 193–196.Google Scholar
  4. Inouchi, N., andSato, H. (1975),Vertical Crustal Deformation Accompanied with the Tonankai Earthquake of 1944, Bull. Geogr. Surv. Inst., Tokyo21, 10–18.Google Scholar
  5. Ishibashi, K. (1976),Re-examination of a Great Earthquake Expected in the Tokai District: Possibility of the ‘Suruga Bay Earthquake’, Abstracts, Seismol. Soc. Japan, 1976 No. 2, 30–34 (in Japanese).Google Scholar
  6. Ishibashi, K.,Specification of a Soon-to-Occur Seismic Faulting in the Tokai District, Central Japan, Based upon Seismotectonics, inEarthquake Prediction (eds. D. W. Simpson and P. G. Richard) (Maurice Ewing Series, IV 1981), pp. 297–332.Google Scholar
  7. Koshiyama, T. (1976),Kokudo Chiriin Kōhō 100, Suppl., 7–8 (in Japanese).Google Scholar
  8. Mogi, K. (1970),Recent Horizontal Deformation of the Earth's Crust and Tectonic Activity in Japan (1), Bull. Earthq. Res. Inst., Tokyo Univ.48, 413–430.Google Scholar
  9. Mogi, K.,Earthquake Prediction Program in Japan, inEarthquake Prediction, (eds. D. W. Simpson and P. G. Richard), (Maurice Ewing Series, IV 1981), pp. 635–666.Google Scholar
  10. Mogi, K. (1982),Temporal Variation of the Precursory Crustal Deformation Just Prior to the 1944 Tonankai Earthquake, J. Seismol. Soc. Japan35, 145–148 (in Japanese).Google Scholar
  11. Sato, H. (1970),Crustal Movements Associated with the 1944 Tonankai Earthquake, J. Geod. Soc. Japan15, 177–180 (in Japanese).Google Scholar
  12. Sato, H. (1977),Some Precursors Prior to Recent Great Earthquakes Along the Nakai Trough, J. Phys. Earth.25, Suppl. S115-S121.Google Scholar
  13. Sekiya, H., andTokunaga, K. (1974),On the Seismicity near the Sea of Enshu, Rep. Coord. Comm. Earthq. Prediction11, 96–101 (in Japanese).Google Scholar
  14. Thatcher, W.,Crustal Deformation Studies and Earthquake Prediction Research, inEarthquake Prediction (eds. D. W. Simpson and P. G. Richard) (Maurice Ewing Series, IV 1981), pp. 394–410.Google Scholar

Copyright information

© Birkhäuser Verlag 1985

Authors and Affiliations

  • Kiyoo Mogi
    • 1
  1. 1.Earthquake Research InstituteUniversity of TokyoTokyoJapan

Personalised recommendations