© GNS Science
The Alpine Fault, which runs up the spine of the South Island, has ruptured five times in the past 1100 years - producing an earthquake of between magnitude 7 and 8 each time.
The Alpine Fault, which runs up the spine of the South Island, has ruptured five times in the past 1100 years - producing an earthquake of between magnitude 7 and 8 each time.
In the past 25 million years, the two sides of the South Island have shifted more than 700 kilometres relative to each other along the Alpine Fault. That is 250km more than previously thought.
The full extent of the movement was masked because the rocks first moved 250km in one direction, then went back the other way - retracing the first 250km and adding a further 450km.
GNS Science earthquake geologist Robert Langridge has been studying why the Alpine Fault is so susceptible to earthquakes - it's since been discovered that it may be the world's fastest-moving known fault line.
The extent of the movement was worked out by researchers from Victoria University and GNS Science, with the findings published in the American Geophysical Union journal G-Cubed.
Comment: Oooh! How lucky! Isn't it LOVELY! Be sure to completely ignore the implications of a phenomenon normally seen over the Arctic appearing in Southern England. Are we soon to expect trite media articles about the splendor of icebergs, complete with polar bears, floating down the Thames?! Oh look! how lovely and lucky we are to see polar bears on the Thames! Now we don't have to go to the zoo! {{triple facepalm}}