UPDATE: Many aftershocks after 5.8 quake

Big quake shakes central New Zealand

Central New Zealand has been shaken awake with a swarm of quakes including a large 5.8 event this morning

Stuff,

21 July, 2013

The majority of the quakes have been centred in the same area off Seddon, Marlborough, that was hit on Friday by a 5.7.

This morning's first quake - 4.2 - struck at 7.04, was at a 10km depth and centred 35km east of Seddon.

It was followed 13 minutes later by the 5.8 shake that was centred 30km east of Seddon at a depth of 19km and then at 7.20 by a 4.3km shake at a depth of 14km and 25km east of Seddon, while a fourth - 4.3 - rattled the region from a depth of 22km at 7.30.

There have been over 30 earthquakes in the same area in total so far this morning with the latest bigger ones being 4.5 magnitude at 9.28am, 5.1 at 10.55am and 4.6 at 12.21pm.

Geonet duty seismologist Dr Anna Kaiser said it's expected they would continue.

"It's quite common to get a shock reaching about four (on the richter scale) before a larger one, like we had before the 5.8 this morning.

"It's also normal to get a series of threes and fours afterwards and about every two minutes or so is common.''

GeoNet's website also crashed this morning due to a high demand from people wanting to see where earthquakes have struck.

The run of earthquakes are a reminder that Wellington is a seismic active area and everyone should always be prepared, she said.

"These quakes this morning are very close to the subduction interface, which is the boundary between the Pacific and Australian plate.''

The aftershocks this morning have ranged from 2.5 to 4.1 - all centred in the same region. While Geonet initially reported quakes in other areas in both islands, it appears they were erroneous recordings sparked by the other quakes. (A full list of the quakes from 5.05am to 9am today is listed below).

There are no reports of damage yet, but Tranz Metro has advised all its services in Wellington have been delayed. Services on the Wairarapa and Johnsonville rail lines have been replaced by buses while track inspections are undertaken.

Both police and fire haven't received any emergency calls.

Rosa Williams, from Newlands and Shiree Palmer, in Otaki, both said on Facebook that the shaking was bigger and stronger than Friday's.

Eastbourne was quite different to being in Thorndon for Friday's earthquake, Erika Scott, said on Facebook.

"This was more a series of shakes and rolls for me and I feel safer than being in the city.''

A Blenheim man described the biggest of the quakes as a strong jolt followed by a rolling motion for about 15 seconds.

Winemaker Peter Yealands said there appeared to be no damage at his Seddon winery.

He was having breakfast at his Seaview home near Seddon when the quake hit, he said.

''It went on for about a minute, it was quite unnerving,'' he said.

There did not appear to be any damage to the winery, although some wine had sloshed out of the tanks on to the floor, he said.

Supervalue Seddon shop assistant Michaela Baillie said a few things fell off the shelves this morning.

''It was quite sharp and scary, it was certainly worse than the quake on Friday.''

Marlborough Civil Defence emergency services officer Gary Spence said there had been no reports of damage, following the quake.

"I've talked to the sector manager from Seddon and it sounds like it was pretty much like Friday, a few things off the shelves in the supermarket, but no injury and no severe damage," Mr Spence said.

US Ambassador to New Zealand David Huebner tweeted that the quake was felt as a "meaningful jolt and roll" in Lower Hutt.

Residents in Khandallah, Wellington, were woken by a sharp jolt, but said it didn't feel as strong as Friday's.

"We felt a single big heave and then there was just a light rumble for about 15 seconds It wasn't big enough to get us out of bed'" a Khandallah woman said.

Another Wellingtonian said "it made me get out of bed and crouch beside it and my husband walked through from the kitchen and joined me pointlessly huddled, so it must have last at least 15 seconds''.

Radio journalist Barry Soper took to Twitter to say the quake made a television fall against the wall at his home.

TODAY'S QUAKES UP (with those over 4 highlighted)

5.05am - 30 km east of Seddon - 3.5

7.04am - 30 km east of Seddon - 4.2

7.17am - 30 km east of Seddon - 5.8

7.20am - 25 km east of Seddon - 4.3

7.22am - 30 km east of Seddon - 4.1

7.25am - 25 km east of Seddon - 3.7

7.30am - 25 km east of Seddon - 4.4

7.33am - 5 km south of Wellington - 2.5

7.35am - 25km east of Seddon - 3.4

7.37am - 25 km east of Seddon - 3.2

7.43am - 25 km east of Seddon - 3.8

7.45am - 25 km east of Seddon - 3.9

7.52am - 25km east of Seddon - 3.3

7.57am - 25 km east of Seddon - 3.4

7.58am - 25 km east of Seddon - 3.4

8am - 25km east of Seddon - 3.6

8.05am - 30 km east of Seddon - 3.3

8.06am - 25 km south-west of Wellington - 3.2

8.08am - 15km east of Murupara - 3.7

8.14am - 30km east of Seddon - 3.1

8.20am - 25km east of Seddon - 3.2

8.32am - 25 km east of Seddon - 3.1

8.37am - 30 km east of Seddon - 3.5

8.56am - 25 km east of Seddon - 2.9

8.59am - 25 km east of Seddon - 2.8

9.07am - 25km east of Seddon - 3.0

9.12am - 25km east of Seddon - 3.0

9.16am - 5km east of Seddon - 2.3

9.18am - 30km east of Seddon - 2.9

9.20am - 25km east of Seddon - 3.1

9.26am - 25km east of Seddon - 2.8

9.28am - 25km east of Seddon - 4.5

9.30am - 30km east of Picton - 2.9

10.04am - 25km east of Seddon - 2.8

10.14am - 25km east of Seddon - 3.2

10.50am - 30km east of Seddon - 3.3

10.55am - 30km east of Seddon - 4.9

11.31am - 25km east of Seddon - 3.1

11.36am - 25km east of Seddon - 2.9

11.45am - 25km east of Seddon - 3.1

11.52am - 25km east of Seddon - 2.7

12.10pm - 25km east of Seddon - 3.0

12.21pm - 25km east of Seddon - 4.6

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