Adams, R.D.; Lensen, G.J.; Strachan, C.M.; Laws, H.R. 1970 Seddon earthquake, New Zealand, April 1966. Wellington: DSIR. DSIR Bulletin 199 35 p.
Abstract: Contents: 1. Adams, R.D. Seismological studies of the Seddon earthquake, 1966 2. Lensen, G.J. Geological aspects of the Seddon earthquake, 1966 3. Strachan, C.M.; Laws, H.R. Report on damage at Seddon, Blenheim, and Wellington after the Seddon earthquake, 1966 Abstract of first paper: An earthquake of magnitude 6.1 occurred in Cook Strait, between the North and South Islands of New Zealand, on 23 April 1966, causing damage to a large number of chimneys in the town of Seddon, and minor damage at Blenheim and Wellington. The epicentre was determined using the values of 8.1 and 4.7 km/s for Pn and Sn wave velocities that have recently been established for New Zealand, but it could not be located with great accuracy because of the limited ranges of azimuth subtended by New Zealand seismograph stations. The best estimate places the epicentre 35 km from Seddon and the focus in the lower crust. A sequence of about 40 aftershocks was recorded during the week following the earthquake. There are indications that the epicentres of the aftershocks spread over a larger area than has been the case for some other New Zealand sequences. (auth.)