People throughout Marlborough ducked for cover early this morning when a 5.7 magnitude earthquake hit the region
The quake at 9.06am, was 8 km deep and was centred 30km east of Seddon, in Cook Strait.
Initial reports on GeoNet said the quake was 5.4 and about 19km deep, but this was later amended to a 5.7 quake, and at the much shallower depth.
People said they had sheltered under desks and in doorways as the quake rolled through the region.
It was also widely felt through the rest of central New Zealand.
There have been no reports of serious damage. A few items fallen off supermarket shelves, large wine tanks had swayed and people said on Facebook their televisions had toppled.
Aftershocks have continued throughout the morning, with smaller earthquakes in the Awatere Valley and the Marlborough Sounds.
Aftershocks are likely to continue for at least 24 hours after the 5.7 earthquake centred in Cook Strait this morning, according to GeoNet scientists.
The 5.7 earthquake was preceded by a mag 2.9 ''foreshock'' in the same location six minutes before the main shock at 9.06am.
There had been numerous aftershocks (17 by late Friday morning) in the region, the largest being a magnitude 3.7 centred 30km east of Seddon.
These were likely to continue until at least tomorrow morning.
Many people had been concerned about the risk of a tsunami after the earthquake, but the blog at geonet.org.nz says it had been much too small.
An offshore earthquake needed to be at least magnitude 7.5 for a tsunami to be considered possible.
The 1855 magnitude 8.2 Wairarapa earthquake was New Zealand's most severe quake since European colonisation, which produced a tsunami with a maximum height of about 11m at Palliser Bay.
It reached a height of 2.4m in central Wellington.
The blog says the region was spared the full force of the earthquake because it struck in the Cook Strait.
A handful of people reported that the quake had a damaging intensity.
Early analysis of the quake has the fault movement as ''reverse faulting'' meaning that each side of the fault is being compressed.
Seddon Supervalue till operator, Carrie Rule said staff and the one customer at the supermarket during the earthquake were a bit shakey.
"She was a good one!
"We're all still a bit shakey but it wasn't too bad, no stock fell of the shelves or anything, but apparently there was a truck in the car park which was shaking back and forth," she said.
I THOUGHT THE ROOF WAS GOING TO CAVE IN
The Warehouse Blenheim manager, Ian Daubney said although there was no damage, he was on the verge of calling an evacuation.
"I thought the roof was going to cave in to be honest. All the lights were shaking and the shelving units were bouncing around.
"It was the best one I've felt in this store and I've been here 20 years," he said.
Mr Daubney called a meeting with the staff, who did a parameter check to make sure there was no damage to the building.
The only items which fell from shelves were soft packaged items.
LIKE A BLOODY ROLLERCOASTER
Lake Grassmere farmer Peter Davison said he had never seen the house buck and shake so much.
''It was like being on a bloody rollercoaster,'' he said.
Mr Davison was looking out the window of his Marfells Beach Rd home when the quake hit.
He had been in Christchurch for the boxing day quake in 2011 and said this one felt far worse.
''I've never felt anything like it,'' he said.
His fishing rods had fallen and lay scattered around his library, blocking the way to the lounge.
Fishing rods were lying all over the floor and the pictures were askew on the walls.
''It's a wooden house and I've never seen the walls move like this.''
There didn't appear to be any serious damage, he said.
Winemaker Peter Yealands said there appeared to be no damage at the Seddon winery.
It was the first major quake for the Yealands Estate winery, on the corner of Seaview and Reserve Rds in Seddon, since it was built in 2008.
Mr Yealands said the winery was built on an area with a fault line through the middle of it and had been designed to withstand a magnitude 8 earthquake.
''The tanks moved a bit and the staff were a bit scared, as you'd expect,'' Mr Yealands said.
''This is the biggest I can recall, it seemed to go for quite a while.''
SAUVIGNON BLANC SLOSHED OUT OF THE TANKS
Chris Darling, a winemaker at Matua's winery in Rapaura, said the wine in the tanks had "sloshed around" a lot after the earthquake, which had felt like a "quick jolt" at the winery.
The tanks were all bolted to the ground, he said, so there was no risk, but the wine could be heard moving around in the full tanks.
Mainly sauvignon blanc, a few litres had sloshed out of some of the tanks, according to workers who were standing next to the tanks, he said. The losses were negligible.
Blenheim New World owner, Ashley Shore said about 100 units fell off the shelves at the store, but nobody was too phased about the shake.
"The team cleaned it up pretty quickly, and there was actually customers in the aisles who just carried on shopping," he said.
Mr Shore said they did not have to evacuate the supermarket.
Blenheim Pak 'n Save co-owner Andrea Boock said nothing had fallen off the shelves at the Blenheim store.
The building, at the Westwood Development, had been built to earthquake regulations.
"Nothing at all has fallen. We're all safe.''
Office workers in Blenheim quickly got under their desks as the first wave hit, followed by a second strong jolt and a third smaller shake within the space of about 20 seconds.
It was felt throughout the whole region and the wider central region.
People in Nelson said they had also been under their desks.
Marlborough District Council chief executive Andrew Besley sent emergency management staff to check the situation in Seddon, the closest township to the earthquake epicentre, a council spokeswoman said.
There have been no reports of rock falls on State Highway 1 near Kaikoura.
A spokeswoman for roading contractor Downer said at 9.55am no one had reported damage on SH1 between Parnassus, near Cheviot, and south of Ward.
KiwiRail has put precautionary restrictions on trains going through tunnels or over bridges after the earthquake, a spokeswoman said.
The restrictions were from Otaki, just north of Wellington to a point just north of Kaikoura, she said.
The restrictions meant trains would travel at slow speed across bridges and through tunnels.
Bridge inspections were being done in Marlborough after the earthquake, Marlborough Roads general manager Frank Porter said.
That was just a precaution, he said, as at this stage Marlborough Roads was not aware of any issues. There have been no reports of any road problems, he said.
Blenheim emergency services have been ''dead quiet'' after the quake.
A Blenheim police spokeswoman said the police station on Main St shook for ages but there had been no reports of damage in the town.
Blenheim St John Ambulance team leader Rebecca Lee said the quake was a ''bloody good one.'' The Seymour St ambulance building had moved around a bit but no calls had come through.
''We've had nothing at all. It's been dead quiet actually,'' Ms Lee said.
Earthquakes often brought anxiety related medical calls, she said.
Blenheim chief fire officer Rob Dalton said the station had been ''quiet as a mouse''.
It was unlikely the station would get any calls if they hadn't already, he said.
Blenheim's highest building, the 5-storey Rangitane House, "swayed a bit" in the earthquake, Rangitane trust receptionist Jamie Fuller said.
The iwi trust is on the fourth floor of the building.
Newly renovated, the building's managers say they have engineers' reports that say it would be safe in major earthquakes.
Rarangi resident Bev Doole said that the quake had not caused any damage at her home.
"It was a bit longer and stronger than the casual shake. A bit of rattling, but nothing off the shelves. It was the first one experienced in my new house and it held up well, thank goodness."
- The Marlborough Express