Skip to main content
Log in

Earthquake prediction and oriented microcracks in rocks

  • Letter
  • Published:

From Nature

View current issue Submit your manuscript

Abstract

VARIATIONS in the ratio of compressional wave velocities and shear wave velocities, presage some earthquakes1. The ratio first decreases, but just before the earthquake it returns to, or rises above, the original value. An attractive model has been proposed by Nur2. Briefly, he suggested that anelastic expansion of the rock (dilatancy) reduced the velocities. With the subsequent rise of the pore pressure of water, the velocity increases again. The increased pore pressure also weakens the rock, resulting in an earthquake. All that effects the velocity of compressional waves more than the velocity of shear waves, giving the apparent variation in their ratio.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. Semenov, A. M., Bull. Acad. Sci. USSR, Phys. solid Earth, 3, 245 (1969); Nersesov, I. A., Semenov, A. N., and Simbireva, I. G., in Eksperimental' naia Seismologiia (edit. by Sadovskii, M. A.), 1 (Nauka, Moscow, 1971); Aggarwal, Y. P., Sykes, L. R., Armbruster, J., and Sbar, M. L., Nature, 241, 101 (1973); Whitcomb, J. H., Garmany, J. D., and Anderson, D. L., Science, 130, 632 (1973).

    Google Scholar 

  2. Nur, A., Bull. seism. Soc. Am., 62, 1217 (1972).

    Google Scholar 

  3. Aggarwal, Y. P., Simpson, D. W., and Sykes, L. R., EOS Trans. Am. geophys. Un., 55, 355 (1974).

    Google Scholar 

  4. McEvilly, T., and Johnson, L., Science, 132, 588 (1973); Bull. Seism. Soc. Am., 64, 343 (1974).

    Google Scholar 

  5. Robinson, R., Wesson, R. L., and Ellsworth, W. L., Science, 184, 1281 (1974).

    Article  ADS  CAS  Google Scholar 

  6. Nur, A., Bell, M. L., and Talwani, P., Proc. Conf. Tectonic Problems of the San Andreas Fault System (edit. by Kovach, R. L., and Nur, A.), (Stanford University Publications, Stanford, 1973).

    Google Scholar 

  7. Gupta, I. N., J. geophys. Res., 78, 6936 (1973).

    Article  ADS  Google Scholar 

  8. Anderson, D. L., Minster, B., and Cole, D., J. geophys. Res. (in the press).

Download references

Author information

Authors and Affiliations

Authors

Rights and permissions

Reprints and permissions

About this article

Cite this article

WANG, CY. Earthquake prediction and oriented microcracks in rocks. Nature 251, 405–406 (1974). https://doi.org/10.1038/251405a0

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1038/251405a0

  • Springer Nature Limited

This article is cited by

Navigation