Geophysics

1989 Edition

Earthquakes: Magnitude, energy, and intensity

  • Seweryn J. Duda
Reference work entry
DOI: https://doi.org/10.1007/0-387-30752-4_6

Development of the Concepts

Preliminaries.

The focus of an earthquake radiates mechanical energy in the form of seismic waves. The radiation of seismic energy during the event continues from a fraction of a second to several tens of seconds. The duration of seismic wave radiation is identical with that of the instantaneous faulting.

The time between two radiation events from a given focus is substantially larger than the radiation duration of a given event. Thus, earthquakes are transient radiation phenomena, and the methods for the determination of the strength of sources radiating transient signals are correspondingly applicable. On this basis the earthquake magnitude scale was introduced. A steady development of the magnitude concept is necessitated by ongoing improvements in seismological instrumentation and in the theories of the focal process and of seismic wave propagation.

A comprehensive review of the magnitude problem was given by Båth (1981), together with an extensive...

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References

  1. Aki, K., 1967, Scaling law of seismic spectrum, Jour. Geophys. Research 72, 1217–1231.Google Scholar
  2. Aki, K., and Richards, P. G., 1980, Quantitative Seismology—Theory and Methods, vols. I and II. San Francisco: W. H. Freeman, 932 p.Google Scholar
  3. ANS, 1966, American National Standard, specification for octave, half-octave, and third-octave band filter sets. New York: American National Standards Institute, Inc., 26 p.Google Scholar
  4. Båth, M., 1973, Introduction to Seismology. Basel and Stuttgart: Birkhäuser Verlag, 395 p.Google Scholar
  5. Båth, M., 1974, Spectral Analysis in Geophysics. Amsterdam-Oxford-New York: Elsevier, 563 p.Google Scholar
  6. Båth, M., 1977, Teleseismic magnitude relations, Annali di Geofis. 30, 299–327.Google Scholar
  7. Båth, M., 1981, Earthquake Magnitude—Recent Research and Current Trends, Earth-Sci. Rev. 17, 315–398.Google Scholar
  8. Bolt, B. A., 1978, Earthquakes—A Primer. San Francisco: W. H. Freeman, 241 p.Google Scholar
  9. Gutenberg, B., and Richter, C. F., 1956, Magnitude and Energy of Earthquakes, Annali Geofisica 9, 1–15.Google Scholar
  10. Hanks, T.C., and Wyss, M., 1972, The use of body wave spectra in the determination of seismic source parameters, Seismol. Soc. America Bull. 62, 561–589.Google Scholar
  11. Harjes, H.-P., and Seidl, D., 1978, Figital recording and analysis of broad-band seismic data at the Graefenberg (GRF)-array, Jour. Geophys. 44, 511–523.Google Scholar
  12. Hurtig, E., and Stiller, H., 1984, Erdbeben und Erdbebengefährdung. Berlin: Akademie-Verlag, 328 p.Google Scholar
  13. Keilis-Borok, V., 1959, On estimation of the displacement in an earthquake source and of source dimensions, Annali di Geofis. 12, 205–214.Google Scholar
  14. Nortmann, R., and Duda, S. J., 1982, The amplitude spectra of P-and S-waves and the body-wave magnitude of earthquakes, Tectonophysics 84, 251–275.Google Scholar
  15. Nortmann, R., and Duda, S. J., 1983, Determination of spectral properties of earthquakes from their magnitudes, Tectonophysics 93, 251–275.Google Scholar
  16. Richter, C. F., 1935, An instrumental earthquake scale, Seismol. Soc. America Bull. 25, 1–32.Google Scholar
  17. Richter, C. F., Elementary Seismology. San Francisco and London: W. H. Freeman, 768 p.Google Scholar
  18. Sarkar, D., and S. J. Duda, 1985, Spectral P-wave magnitudes, Aki's w-square model and source parameters of earthquakes, Tectonophysics 118, 175–193.Google Scholar
  19. Vanek, J., Zatopek, A., Karnik, V., Kondorskaya, N. V., Riznichenko, Yu. V., Savarensky, E. F., Solov'yov, S. L., and Shebalin, N. V., 1962, Standardization of magnitude scales (in Russian), Akad. Nauk CCCP, Izv. Ser. Geofiz. 2, 153–158.Google Scholar
  20. Vanek, J., N. V. Kondorskaya, and Christoskow, L. V., 1980, The Earthquake Magnitude in Seismological Practice-PV-and PVs-Waves (in Russian). Sofia: Bulgarian Academy of Sciences, 263 p.Google Scholar

Copyright information

© Van Nostrand Reinhold 1989

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  • Seweryn J. Duda

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