The Dunedin earthquake, 9 April 1974

Part 1: seismological studies

  • R. D. Adams DSIR Seismological Observatory, Wellington, New Zealand
  • R. J. Kean DSIR Seismological Observatory, Wellington, New Zealand

Abstract

The Dunedin earthquake of 9 April, 1974 was of magnitude 5.0, and is the largest known to have originated in eastern Otago. The shock was centred about 10 km south of the city centre, with a shallow focus, probably about 20 km deep. Damage to a value of about $250,000 occurred, and many brick chimneys were broken or damaged in the worst affected areas, where the intensity reached MM VII. The areas of greatest damage were the southern suburbs, on alluvial soils, where results from a survey of natural seismic noise show strong amplification effects due to the unconsolidated nature of the ground.

References

Adams, R. D. 1974: Statistical Studies of Earthquakes Associated with Lake Benmore, New Zealand. Engineering Geology. Accepted for publication.

Adams, R. D., Muir, M. G. and Kean, R. J., 1972: Te Aroha Earthquake, 9 January, 1972. Bull. N.Z. Soc. Earthquake Eng., Vol. 5, 54-8.

Adams, R. D., Robinson, R. and Lowry, M. A. 1974: A Micro-earthquake Survey of the Benmore-Pukaki Region; February-March, 1973. Report No. 86. Geophysics Division, D.S.I.R., Wellington.

Benson, W. N. 1968: Dunedin District. 1 : 50 000. N.Z. Geological Survey Miscellaneous Series Map 1. D.S.I.R., Wellington.

McKellar, I. C. 1966: Sheet 25, Dunedin, Geological Map of New Zealand 1 : 250 000. D.S.I.R., Wellington.

Scholz, C. H., Rynn, J. M. W., Weed, R. W. and Frohlich, C. 1973: Detailed Seismicity of the Alpine Fault Zone and Fiordland Region, New Zealand. Bull. Geol. Soc. Amer. 84, 3297-316.

Shebalin, N. V. 1961: Ballnost' , Magnituda i Glubina Ochaga Zemlyetracenii. In "Zemlyetraceniya v SSSR". Academy of Sciences, Moscow.

Published
1974-09-30
How to Cite
Adams, R. D., & Kean, R. J. (1974). The Dunedin earthquake, 9 April 1974. Bulletin of the New Zealand Society for Earthquake Engineering, 7(3), 115-122. https://doi.org/10.5459/bnzsee.7.3.115-122
Section
Articles