Earthquake swarm rattles Wairoa

Last updated 10:09 23/02/2013
Wairoa quakes

SHAKY GROUND: This Geonet graphic shows how widely the quakes were felt across Hawke's Bay.

Related Links

Anniversary night aftershock for Christchurch

Relevant offers

National News

Commerce Commission to interview Auckland property coach A crash on SH1 in Tawa caused major congestion Southland discus thrower Marshall Hall throws himself into world championship reckoning Aussie mother Adele Barbaro to livestream childbirth Four more medals for Lisa Carrington and kayaking team-mates in successful World Cup regatta Government accused of playing politics with Wellington's transport future Myrtle rust infected sites grow to 25 across country Pack your own meals, Hutt city councillor Campbell Barry tells colleagues Jennifer O'Connell looking to build on three minute Southern Steel debut in national netball league Sarah Trotman: The importance of successful female role models

The Hawke's Bay town of Wairoa has been rocked by more than 20 earthquakes in the past 24 hours - a pattern that could be in play for days, scientists say.

According to Geonet, the strongest shakes only measured "light" on the intensity scale but the tremors were unlikely to let up for a couple of days.

Geonet data centre manager Kevin Fenaughty said the event was known as an "earthquake swarm."

Earthquake swarms are events where a local area experiences sequences of many earthquakes striking in a relatively short period of time.

"This activity really burst into life yesterday evening soon after 5.30pm, with six noticeable quakes occurring within 45 minutes," he said.

Since then, further pulses of activity were recorded between 9.45pm and 10pm, 12.45am and 1.45am, and most recently between 7.20am and 9.30am.

A 4.8 was recorded at 7.21 this morning, at a depth of 67km, just 40km south of Wairoa.

According to reports, it was felt as far north as Waitoa, near Morrinsville, and as far south as Poukawa, below Havelock North.

Fenaughty said the duration of a swarm could not be predicted, but past experience with this part of New Zealand suggests that this one is of the order of days.

It could then recur at a later date after a break in the activity.

Another characteristic of swarms was that no single earthquake in the sequence was obviously the main shock.

It is unlikely the quakes would get bigger than the 4.8 recorded to date, but it could not be ruled out, Fenaughty said.

Ad Feedback

- Stuff

Special offers

Featured Promotions

Sponsored Content