Major quake felt throughout NZ

Updated at 12:54 am on 4 July 2012

A major earthquake rattled parts of New Zealand on Tuesday night.

GeoNet says the magnitude 7 quake hit the west coast of the North Island at 10.36pm.

The quake was centred out to sea at a depth of 230km, 60km south of Opunake in Taranaki and 170km northwest of the capital Wellington.

The long, rolling tremor was felt from the Bay of Plenty in the North Island to Dunedin in the South Island and lasted about 30 seconds.

No tsunami warning has been issued and there have been no reports of serious damage.

GeoNet said the quake was felt widely throughout the country due to its depth. However, seismologist Lara Bland told Radio New Zealand if there are any aftershocks, they should be small.

"There is no risk of a tsunami from an earthquake like this - it's occurred too deep for the sea floor to be disturbed.

"For an earthquake this size you might see a few aftershocks. Given that they will be smaller and off the coast, they might not be felt as widely at all."

Opunake Beach Holiday Park manager Dean Marden told Radio New Zealand he was woken up by the tremor.

"My wife and I lay in bed feeling like someone was gently shaking the bed and the house, then suddenly after what seemed like five seconds the whole room felt like it was rolling."

Mr Marden says some things fell over in his house, but otherwise they are okay.

A shallow quake of magnitude 3.9 occurred in Canterbury at 11.07pm. GeoNet says the tremor was 20km east of Christchurch at a depth of 9km. The magnitude 7 quake was also felt in the city which was badly damaged in a devastating quake in February last year.

No damage to gas rigs

Shell Exploration says the 7-magnitude quake did not damage the Maui A and Maui B drilling platforms off the Taranaki coast.

The company says as part of standard procedures after an earthquake checks were made at crucial places around the rigs and no damage was found.

However, Shell says workers on the Maui A rig say they felt the quake and described it as one of the biggest they have experienced.

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