7.0 earthquake felt in Wellington

Train lines across Wellington had to be inspected through the night after a 7.0-magnitude quake hit the lower North Island.

Track inspections were completed before the morning trains began on all but the Kapiti line, which was not given clearance until 6am.

There were minor delays for early morning Kapiti commuters and taxis were provided.

Inspections of train lines are routine after an earthquake.

AMP NZ office chief executive Scot Pritchard said a small water leak had occurred at the AXA Centre overnight on The Terrace which had stopped lifts.

He said it was unclear whether the issue was quake related but expected lifts to be back up and running over the next few hours.

The quake hit at 10.36pm. GeoNet reported it was centred 230km deep and was 170km northwest of Wellington.

It was a long, rolling quake felt throughout the lower North Island and upper South Island.

The earthquake registered 7.0 on the Richter scale - slightly smaller than the 7.1 in Canterbury in September 2010.

Some people were reported to have moved to higher ground on the Horowhenua coast, but a Civil Defence spokesman said the risk of a tsunami was low as the quake struck so deep.

The first quake was followed nine minutes later by a 4.6 shake at the same depth, 70km south of Opunake.

GNS Science duty seismologist Lara Bland said the 7.0 quake was the largest to strike the Taranaki Bight area for the past 100 to 120 years.

It was related to the subduction zone where the Pacific tectonic plate was being driven under the Australian plate, she said.

The quake probably happened on the Pacific plate, which dipped down deeply, she said, occurring because the plate was hard and brittle.

That was also partly why it had been felt so widely, as the energy travelled "efficiently" back up the plate to the surface.

It was a good-sized shake but the depth and distance offshore limited its impact, Bland said.

While large quakes in the area weren't unheard of, "they aren't often that big," she said.

Magnitude-6.0 quakes had occurred in the area over the years.

GNS would try to image the behaviour of the fault, but given the lack of damage or injuries it would probably not look much more deeply into the quake.

Partly that was because many scientists were still tied up working on the Canterbury quakes.

Marea Faigan, from near Inglewood, in Taranaki, said she had never felt anything like it in her life. "It just kept going and going," she said. "The cupboards were rattling and I grabbed hold of the door frame to steady myself."

New World Chaffers duty manager Mark Huddleston said no breakable items fell off shelves at the central Wellington supermarket but small items such as tea bags and painkillers tumbled to the aisles.

Have you or your building been affected by the earthquake? Email web@dompost.co.nz

The Dominion Post