7.1 earthquake: more to come, scientists warn Last updated 15:47 06/09/2010
LATEST: History suggests Saturday's destructive 7.1 Canterbury earthquake could be a trigger for a series of major earthquakes which New Zealand must prepare for, scientists say.
Victoria University's geophysics professor Euan Smith said Saturday morning's magnitude 7.1 quake did some things "as expected" but "had some surprises as well."
He said policy regarding unreinforced masonry structures should now become "urgent" because a 1929 west Canterbury magnitude 7 earthquake turned out to be the first of a series of seven major, magnitude greater than 7, earthquakes over the next 13 years.
The series included the second and third largest earthquakes in European times - the magnitude 7.8 Buller and Hawke's Bay earthquakes.
The series ended with two magnitudes 7.2 and 7.0 earthquakes in the Wairarapa in 1942...........
Big aftershock could still be coming
Updated 7:13 PM Monday Sep 6, 2010
The rate of aftershocks following Saturday's magnitude 7.1 earthquake appears to be lower than usual for a quake of that size, but people around damaged buildings in Canterbury should still be taking extreme care, says an expert.
The aftershocks could be big - within one order of magnitude of the original quake - so there is still the chance of a magnitude 6 shake hitting the un-reinforced masonry around Christchurch and in surrounding towns of mid-Canterbury.