Geologists find fault in optimism on alpine quake risk
Canterbury University earthquake researchers believe the latest study on the frequency of major Alpine Fault earthquakes is too optimistic. Scientists from GNS Science, Otago University's geology department, Western Washington University's geology department and Nevada University's seismological laboratory recently found that the southern section of the 650-kilometre-long fault, near Haast, appears to rupture on average once every 480 years. Previous investigations have suggested the fault breaks about every 300 years. The last great quake, of about magnitude 8.0, was in 1717, suggesting the next one could be due soon. Lead author Kelvin Berryman, of GNS Science, said the 15-year study – published in this month's Bulletin of the Seismological Society of America – had provided "potentially some breathing space, that we're not as close to rupture as is sometimes assumed".