New Zealand Earthquakes

Each year some four hundred significant earthquakes are recorded in New Zealand, of which roughly one hundred are likely to be noticed without instruments. The balance is recorded by seismological instruments, but is not of sufficient importance to warrant public notice.

The earliest known record of an earthquake in New Zealand is found in cook's journals (1769-70). The earliest detailed record of a destructive earthquake is of one which shook Wellington on 19 October 1848, killing 3 people and doing considerable damage to buildings. This quake was centred in the Awatere Valley, Marlborough.

The biggest New Zealand earthquake in historical times was the Wellington earthquake of 23 January 1855, with a magnitude of about 8 on the Richter scale. This quake was felt over an area of about 940,000 sq km and tilted a block of land 50m wide and 190km long. The highest uplift of 3m occurred on the coast at Mukamuka, east of Wellington. In Wellington itself the uplift was 1.5m; and great stretches of shore became permanently exposed. The centre lay along the Wairarapa Fault, and the horizontal movement on this fault is estimated to have been at least 12m compared with about 6m for the 1906 San Francisco earthquake. Despite this huge movement, only 5 pakehas died in the quake, because Wellington was still sparsely populated at that stage. The number of Maoris killed was not ascertained...