Scientists say the last major Alpine Fault earthquake, in 1717, brought long-term disruption across the South Island and “there will be a similar earthquake soon”.
The 1717 quake is estimated to have had a magnitude of around 8.1, according to a special anniversary edition of the New Zealand Journal of Geology and Geophysics, published on Tuesday. That estimate comes from evidence for the ground breaking along 380km of the South Island.
“Land on the south-eastern side of the fault moved up relative to the north-western side in most places and 7–8 metres south in a matter of seconds,” an editorial said.