Surface wave magnitudes of some New Zealand earthquakes 1901-1988

  • D. J. Dowrick DSIR Physical Sciences, Lower Hutt, New Zealand
  • E. G. C. Smith DSIR Geology and Geophysics, Wellington, New Zealand


This paper gives a list of magnitudes on the surface wave scale for a selection of larger New Zealand earthquakes that occurred in the period 1901-1988. Most of the events considered were of shallow origin h < 45 km, and the magnitudes ranged from about 5 to 7.8. The Analysis of Variance method of statistical analysis was used to correct the large set of station observations so as to provide consistent mean magnitudes for each event. The resulting station terms and standard errors are given. Comparisons made between the results of this study and the relatively few previous Ms determinations show little change except for one or two important events. In particular the magnitude of the 1968 Inangahua earthquake was found to be 7.4 (± 0.07), which is somewhat greater than previous estimates.


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How to Cite
Dowrick, D. J., & Smith, E. G. C. (1990). Surface wave magnitudes of some New Zealand earthquakes 1901-1988. Bulletin of the New Zealand Society for Earthquake Engineering, 23(3), 198-210.