Springer Nature is making Coronavirus research free. View research | View latest news | Sign up for updates

Temporal variation of codaQ during Hualien earthquake of 1986 in eastern Taiwan

  • 51 Accesses

  • 12 Citations


The May 20, 1986, Hualien earthquake sequence occurred on the northeastern coast of Taiwan. TheM=6.1 (GS mb) mainshock was followed by a large number of closely-clustered aftershocks with the largest being anM=5.5 event. One seismic station, TWD of the Taiwan Telemetered Seismographic Network, is located in the surface projection of the source region and provides excellent recordings of the entire earthquake sequence. These recordings, plus events occurring in the same source area preceding the mainshock, offer a unique opportunity to study the spatial and temporal variations of codaQ in a region of active subduction. A simple technique is devised that uses the envelope of the coda waveform to enable a quick determination of the codaQ from drum records. For recordings with a peak power at about 8 Hz, the following findings have been obtained: 1. The ambient codaQ near an active subduction region was as low as 145; 2. There was no significant decrease in codaQ within the period beginning one year and four months prior to the mainshock; 3. There was a significant drop of codaQ immediately after the mainshock; this drop lasted approximately two days before returning to the ambient level; 4. CodaQ values varied with focal depth.

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


  1. Aki, K. (1969),Analysis of the seismic coda of local earthquakes as scattered waves, J. Geophys. Res.74, 615–631.

  2. Aki, K. (1980a),Attenuation of shear-waves in the lithosphere for frequencies from 0.05 to 25 Hz, Phys. Earth Planet. Inter.21, 50–60.

  3. Aki, K. (1980b),Scattering and attenuation of shear waves in the lithosphere, J. Geophys. Res.85, 6496–6504.

  4. Aki, K. andB. Chouet (1975),Origin of coda waves: Source, attenuation, and scattering effects J. Geophys. Res.80, 3322–3342.

  5. Ashby, M. F. andS. D. Hallman (1986),The failure of brittle solids containing small cracks under compressive stress state, Acta Metall.34, 497–561.

  6. Ashby, M. F. andC. G. Sammis (1988),The damage mechanics of brittle solids in compression, submitted to Acta Metall.

  7. Chen, K.-C. andJ.-H. Wang (1986),The May 20, 1986 Hualien, Taiwan earthquake and its aftershocks, Bull. Inst. Earth Sci., Academia Sinica6, 1–14.

  8. Chouet, B. (1976),Source, scattering, and attenuation effects in high frequency seismic waves, Ph.D. Thesis, Massachusetts Institute of Technology, Cambridge, Massachusetts.

  9. Chouet, B. (1979).Temporal variation in the attenuation of earthquake coda near Stone Canyon, California, Geophys, Res. Lett.6, 143–146.

  10. Chouet B., K. Aki, andM. Rsujiura (1978),Regional variation of the scaling law of earthquake wave spectra, Bull. Seismol. Soc. Am.68, 49–79.

  11. Gusev, A. A. andV. K. Lemzikov (1985),Properties of scattered elastics waves in the lithosphere of Kamchatka: Parameters and temporal variation, Tectonophys.112, 137–153.

  12. Herrmann, R. B. (1980),Q estimate using the coda of local earthquakes, Bull. Seismol. Soc. Am.70, 447–468.

  13. Horii, H. andS. Nemat-Nasser (1986),Brittle failure in compression: Splitting, faulting, and brittleductile transition, Phil. Tran. Roy. Soc. A319, 337–374.

  14. Hsu, T. L. (1954),On the geographical features and the recent uplifting movement of the coastal range, eastern Taiwan, Bull. Geol. Surv. Taiwan7, 9–18.

  15. Jin, A. (1981),Duration of coda waves and the backscattering coefficient. Paper presented at the Symposium on Seismology in China, State Seismol. Bur., Shanghai, China.

  16. Jin, A. andAki, K. (1986),Temporal changes in coda Q before the Tangshan earthquake of 1976 and the Haicheng earthquake of 1975, J. Geophys. Res.91, 665–673.

  17. Kopnichev, Y. F. (1977),The role of multiple scattering in the formation of a seismogram's tail, Izv. Acad. Aci. USSR Phys. Solid Earth. Engl. Transl. 13, 394–398.

  18. Lee, W. H. K., K. Aki, B. Chouet, P. Johnson, S. Marks, J. T. Newberry, A. S. Ryall, S. W. Stewart, andD. M. Tottingham (1986),A preliminary study of coda Q in California and Nevada, Bull. Seism. Soc. Am.76, 1143–1150.

  19. Liaw, Z.-S., C. Wang, andY. T. Yeh (1986),A study of aftershocks of the 20 May 1986 Hualien earthquake, Bull. Inst. Earth Sci., Academia Sinica6, 15–27.

  20. Nemat-Nasser, S. andH. Horii, (1982),Compression induced nonplanar crack extension with application to splitting, extension, and rockburst, J. Geophys. Res.87, 6805–6821.

  21. Novelo-Casanova, D. A., E. Berg, V. Hsu, andC. E. Helsley (1985),Time-space variation seismic S-wave coda attenuation (Q) and magnitude distribution for the Pelatan earthquake, Geophys. Res. Lett.12, 789–792.

  22. Peng, J. Y., K. Aki, B. Chouet, P. Johnson, W. H. K. Lee, S. Marks, J. T. Newberry, A. S. Ryall, S. W. Stewart, andD. M. Tottingham (1987),Temporal change in coda Q associated with the Round Valley, California, earthquake of November 23, 1984, J. Geophys. Res.92, 3507–3526.

  23. Rautian, T. G. andV. I. Khalturin (1978),The use of coda for determination of the earthquake source spectrum, Bull. Seism. Soc. Am.68, 923–940.

  24. Sammis, C. G. andM. F. Ashby (1986),The failure of brittle porous solids under compressive stress states, Acta Metall.34, 511–526.

  25. Sato, H. (1977),Energy propagation including scattering effects: Single isotropic scattering approximation, J. Phys. Earth25, 27–41.

  26. Sato, H. (1978),Mean free path of S-waves under the Kanto district of Japan, J. Phys. Earth26, 185–198.

  27. Sato, H. (1979),Wave propagation in one-dimensional inhomogeneous elastic media, J. Phys. Earth27, 455–466.

  28. Sato, H. (1984),Attenuation and envelope formation of three-component seismograms of small local earthquakes in randomly inhomogeneous lithosphere, J. Geophys. Res.89, 1221–1241.

  29. Sato, H. (1986),Temporal change in attenuation intensity before and after the Eastern Yamanashi earthquake of 1983 in central Japan, J. Geophys. Res.91, 2049–2061.

  30. Shin, T.-C., W.-J. Su, andP.-L. Leu (1987),Coda-Q estimates for Taiwan Area, Bull. Geophys., Natl. Central Univ.27/28, 95–110.

  31. Singh, S. andR. Herrmann (1983),Regionalization of crustal coda Q in the continental United States, J. Geophys. Res.88, 527–538.

  32. Tsai, Y. B., T. L. Teng, J. M. Chiu, andH. L. Liu (1977),Tectonic implications of seismicity in the Taiwan region, Mem. Geol. Soc. China2, 13–41.

  33. Tsujiura, M. (1978),Spectral analysis of the coda waves from local earthquakes, Bull. Earthq. Res. Inst., Univ. Tokyo.53, 1–48.

  34. Tsukuda, T. (1985),Coda Q before and after a medium-scale earthquake, Paper presented at the 23rd General Assembly, Int. Assoc. of Seismol. and Phys. of the Earth's Inter., Tokyo, Japan.

  35. Wang, J. H., C. C. Liu, K. C. Chen, andY. S. Cheng (1985),Taiwan Telemetered Seismographic Network (in Chinese). Proc. Seminar Commemor. 50th Anniver. Great Hsinchu-Taichung Earthq., 1935, 124–136.

  36. Wu, R. S. (1984),Seismic wave scattering and the small-scale inhomogeneities in the lithosphere, Ph.D. Thesis, Mass. Inst. of Technol., Cambridge, Mass., U.S.A.

  37. Wyss, M. (1985),Precursors to large earthquakes, Earthq. Predict. Res.3, 519–543.

Download references

Author information

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Wang, J.H., Teng, T.L. & Ma, K.F. Temporal variation of codaQ during Hualien earthquake of 1986 in eastern Taiwan. PAGEOPH 130, 617–634 (1989).

Download citation

Key words

  • CodaQ
  • envelope decay curve
  • temporal variation