Reassurance after earthquake prediction

Scientists are reassuring people that earthquake activity in New Zealand – including three magnitude 4 quakes today - remains normal.

Their message comes as many Kiwis are feeling on edge today, mindful of the prediction of a large South Island quake by "Moon Man" Ken Ring.

There has been a succession of smaller earthquakes today, the largest a 4.6 earthquake that struck 10km southwest of Twizel at 1.10pm.

A 4.3 quake in the same area followed at 1.33, then another at 1.34.

GNS principal scientist Kelvin Berryman said the quakes were on the Ostler fault, a fault line that hadn’t shown anything major for 3000 years.

“The 4.6 would have triggered the other two, that does happen from time to time,” he said.

“Normally these things wouldn’t get very much attention, but everyone is very sensitised to earthquakes at the moment.

Ring’s prediction for a quake to hit just before noon today did not happen.

The Twizel quakes, and a 4.7 magnitude quake, 210km deep at 9.34pm last night in Hawera were unrelated to the Christchurch activity, Berryman said.

The scientist said March 20 in Christchurch was on course for a "standard day", with aftershocks remaining well-behaved and getting less frequent and less intense.

"There still remains a possibility (around a five per cent chance) magnitude 5 or larger earthquake could occur in the Canterbury area today, so be prepared," he said.

Scientists would be showing solidarity by continuing with their normal work, as would engineers  and others involved in the clean-up.

Ring made his prediction of a "quake for the history books" on September 7, four days after the first Canterbury earthquake on the site.

He wrote "the morning of 20 March 2011 sees the South Island again in a big earthquake risk".

At 9.44am the moon would be at its closest point to earth for 2011, he said.

"All factors should come together for a moon-shot straight through the centre of the earth and targeting NZ. The time will be just before noon. It could be another for the history books."

The prediction saw thousands of Christchurch residents leave the city, or stockpile goods in case of a quake.

Ring has drawn widespread criticism in the media and from the public, though he says many others have shown him support.