pure and applied geophysics

, Volume 124, Issue 4–5, pp 957–973 | Cite as

Comparison of a complex rupture model with the precursor asperities of the 1975 HawaiiMs-7.2 earthquake

  • D. Harvey
  • M. Wyss


A simplified multiple source model was constructed for the 1975 HawaiiMs=7.2 earthquake by matching synthetic signals with three component accelerograms at two stations located approximately 45 km from the epicenter. Six major subevents were identified and located approximately. The signals of these are larger by factors of 1.4 to 3.2 than that of theML=5.9 foreshock which occurred 70 minutes before the main rupture and also triggered the SAM-1 recorders at the two stations. Dividing the rupture length (40 km) by the duration of strong ground shaking (∼ 50 sec) an, average rupture velocity of 0.8 km/sec (about 25% of S-velocity) is obtained. Thus it is likely that the rupture stopped between subevents. The approximate epicenters of the 6 major subevents, and of the foreshock, support the hypothesis that they were located in high stress asperities which rupture during the main shock, except for the last events which is interpreted as a stopping phase generated at a barrier. These asperities have been previously defined on the basis of differences in the precursor pattern before the mainshock. Thus, it appears that both the details of the precursors and of the main rupture depended critically on the heterogeneous tress distribution in the source volume. This suggests that main rupture initiation points and locations of high rupture accelerations may be identified before the mainshock occurs, based on precursor anomaly patterns. A satisfactory match of synthetic signals with the observations could be obtained only if the aximuth of the fault plane of subevents was rotated from N60°E to N90°E and back to N30°E. These orientations are approximately parallel to the nearest Kilauea rift segments. Hence the slip directions and greatest principal stresses were oriented perpendicular to the rifts everywhere. From this analysis and other work, it is concluded that this fault surface consisted of three types of segments with different strength: hard asperities (radius ≈ 5 km), soft but ‘brittle’ segments between the asperities (radius ≈ 5 km), and a ‘viscous’ half (10×40 km) which slipped during the mainshock, but where microearthquakes and aftershocks are not common.

Key words

Hawaii multiple rupture asperities 


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  1. Aki, K. (1979),Characterization of barriers on an earthquake fault, J. Geophys. Res.84 8140–6148.Google Scholar
  2. Aki, K. (1984),Asperities, barriers, characteristic earthquakes and strong motion prediction. J. Geophys. Res.89 5867–5872.Google Scholar
  3. Ando, M. (1979),The Hawaii earthquake of November 19, 1975: Low dip angle faulting due to forceful injection of magma, J. Geophys. Res.84, 7616–7626.Google Scholar
  4. Aviles, C. A., Scholz, C. H. andBoatwright, J. (1986),Fractal analysis applied to characteristic segments of the San Andreas fault, Bull. Seism. Soc. Amer., in press.Google Scholar
  5. Chapman, C. H., (1978),A new method for computing synthetic seismograms, Geophys. J. R. Astr. Soc.54, 481–518.Google Scholar
  6. Bilham, R. andWilliams, P. (1985),Sawtooth segmentation and deformation processes on the Southern San Andreas fault, California, Geophys. Res. Lett.12, 557–560.Google Scholar
  7. Deschamps, A., Gandemer, Y. andCisternas, A. The El Asnam, Algeria, earthquake of 10 October 1980: Multiple-source mechanism determined from long period records, Bull. Seism. Soc. Am.72, 1111–1128.Google Scholar
  8. Fukao, Y. andFurumoto, M. (1975),Foreshocks and multiple shocks of large earthquakes, Phys. Earth Planet. Interiors7, 147–153.Google Scholar
  9. Furumoto, A. S. andKovach, R. L., (1979),The Kalapana earthquake of November 29, 1975; An intraplate earthquake and its relation to geothermal processes, Phys. Earth Planet. Interiors18, 197–208.Google Scholar
  10. Hartzell, S. H. andHeaton, T. H. (1983),Inversion of strong ground motion and the teleseismic waveform data for the fault rupture history of the 1979 Imperial Valley California, Earthquake, Bull. Seism. Soc. Am.73, 1553–1584.Google Scholar
  11. Harvey, D. J. (1981),Seismogram synthesis using normal mode, superposition: the locked mode approximation. Geophys. J. R. Astr. Soc.66, 37–69.Google Scholar
  12. Houston, H. andKanamori, H. (1983),Rupture process of great earthquakes at short periods, abstract EOS64, 771.Google Scholar
  13. Johnston, A. C., Wyss, M., Koyanagi, R. andHabermann, R. E. (1982),P-wave travel times: Stability and change in the source volume of the M=7.2 Hawaii earthquake of 1975, J. Geophys. Res.87, 6889–6906.Google Scholar
  14. Klein, F. W. (1981),A linear gradient crustal model for South Hawaii Bull. Seismol Soc. Am.71, 1503–1510.Google Scholar
  15. Kanamori, H. andStewart, G.S. (1978),Seismological aspects of the Guatemala earthquake of February 4, 1976, J. Geophys. Res.83, 3427–3434.Google Scholar
  16. Mori, J., (1984),Short-and long-period subevents of the 4 February 1965 Rat Islands earthquake. Bull. Seismol. Soc. Am.74, 1331–1348.Google Scholar
  17. Rial, H. A. (1984),The Caracas, Venezuela, earthquake of July 1967: A multiple-source event. J. Geophys. Res.83, 5405–5414.Google Scholar
  18. Rojahn, C. andMorrill, B. J. (1977),The island of Hawaii earthquake of November 19, 1975: Strong motion data and damage reconnaissance report, Bull. Seismol. Soc. Am.64, 493–516.Google Scholar
  19. Swanson, D. A., Duffield W. A. andFiske, R. S. Displacement of the south flank of Kilauea Volcano: the result of forceful intrusion of magma into the rift zones. U. S. Geological Survey, Prof. Paper,963.Google Scholar
  20. Tilling, R. I., Koyanagi, R. Y., Lipman, P. W., Lockwood, J. P., Moore, J. G. andSwanson, D. A. (1976),Earthquake and related catastrophic events, island of Hawaii, November 29, 1975: A preliminary report. U. S. Geological Survey Circular740.Google Scholar
  21. Trifunac, M. D. andBrune, J. N. (1970),Complexity of energy release during the Imperial Valley, California, earthquake of 1940 Bull. Seism. Soc. Am.60, 137–160.Google Scholar
  22. Wu, F. T. andKanamori, H. (1973),Source mechanism of February 4, 1965, Rat Island earthquake, J. Geophys. Res.78, 6082.Google Scholar
  23. Wyss, M. andBrune, J. N. (1967),The Alaska earthquake of 28 March 1964: A complex multiple rupture. Bull. Seism. Soc. Am.57, 1017–1023.Google Scholar
  24. Wyss, M., Klein, F. W. andJohnston, A. C. (1981a),Precursors to the Kalapana M=7.2 earthquake, J. Geophys. Res86, 3881–3900.Google Scholar
  25. Wyss, M., Johnston, A. C. andKlein, F. W. Multiple asperity model for earthquake prediction. Nature289, 231–234.Google Scholar
  26. Wyss, M. (1986),Seismic quiescence precursor to the 1983 Kaoiki (M=6.6), Hawaii, earthquake. Bull. Seism. Soc. Am., in press.Google Scholar
  27. Zhou, H.-L., Allen, C. R. andKanamori, H. (1983)Rupture complexity of the 1970 Tonghai and 1973 Luhno earthquakes, China, from P-wave inversion, and relationship to surface faulting. Bull. Seism. Soc. Am.73 1583–1597.Google Scholar
  28. Zuniga, F. R., M. Wyss andM. E. Wilson (1986),Apparent stresses, stress drops and amplitude ratios of earthquakes preceding and following the 1975 Hawaii 17 s=7.2 main shock. Bull Seism. Soc. Am., in press, 1986.Google Scholar

Copyright information

© Birkhäuser Verlag 1986

Authors and Affiliations

  • D. Harvey
    • 1
  • M. Wyss
    • 1
  1. 1.Cooperative Institute for Research in Environmental SciencesUniversity of ColaradoBoulder

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