A RECORD number of babies were born in the aftermath of the powerful 7.1-magnitude quake that rocked New Zealand on the weekend, hospital officials say.

A spokeswoman for Christchurch Women's hospital said 21 babies were born at its maternity ward in the 24 hours after the tremor, which damaged buildings and roads in New Zealand's worst quake disaster in decades.

"In the 24 hours post earthquake, 21 babies were born...and that's a record for a Saturday,'' a hospital spokeswoman told Agence France-Presse.

The first newborn arrived within 10 minutes of the pre-dawn quake, which saw roads gridlocked as residents rushed to higher ground to escape a potential tsunami.

Meanwhile, Miriam Garcia was in labour at home when the quake struck and had just decided to head for the hospital.

"I couldn't believe the timing," the new mum, who delivered baby Amelia about two hours later, told The Press newspaper.

"I had a lot of false labours in the weeks before and I was thinking, 'Now it's happening'."

Danika Weeks was already in labour in the hospital when the earth rocked.

"The first thing I remember was seeing the re-sus (resuscitation) machines sort of coming towards us, like two horses racing towards us," she told TVNZ.

"I was sort of like, 'Gosh did we cause this? You know, is this part of it? Does the earth move?'," she said.

Baby boy Lincoln arrived safely, and first-time mum Ms Weeks said she suspected the shock of the quake was enough to jolt others into delivering their newborns.

"If you weren't in labour already it definitely would've brought it on for sure," she said.

Of the experience, she said the quake "made it all the more amazing, really, that we went through two sorts of trauma in the one day".



Earthquake tears new 3.5m fault line on Earth's surface

The powerful earthquake that smashed buildings, cracked roads and twisted rail lines in Christchurch also ripped a new 3.5m-wide fault line in the Earth's surface.

At least 500 buildings were destroyed in the 7.1-magnitude quake that struck New Zealand at 4.35am on Saturday near the South Island city of about 400,000 people.

The earthquake cut power across the region, roads were blocked by debris, and gas and water supplies were disrupted.

Christchurch Mayor Bob Parker yesterday said power had been restored to 90 per cent of the city and water supply had resumed for all but 15 to 20 per cent of residents.

Portable toilets and tanks of fresh water had been placed around the city.

As the clean-up continued yesterday, the exodus began, with dozens of Australian tourists fleeing, thankful the quake had hit early in the morning rather than during the day.

Melbourne resident Donna Van Niekerk, who was in Christchurch with husband Lionel and daughter Darcy, said the quake was like "being on a boat in 20-foot waves".

"It was massive, the building was swaying slowly," she said. "I just got thrown to the other side of the room. We were just waiting for the building to collapse."

Kevin Tracey and wife Susan, from Ipswich, were sleeping in a hotel 50m from some of the worst damage.

It was the first night of Mr Tracey's first overseas holiday.

"It just shook," he said. "It rattled the front door, I thought somebody was trying to get in."

Teams of building inspectors searched Christchurch's CBD for structural damage, while New Zealand's Government postponed school until Wednesday and most surgery was cancelled in the city's hospitals.

Canterbury University geology professor Mark Quigley said "a new fault" had ripped across the globe and pushed surface areas up.

He said the quake was caused by the collision of the Pacific and Australian tectonic plates.

"One side of the Earth has lurched to the right . . . up to 11 feet (3.5m) and in some places been thrust up," Mr Quigley said.

"The long linear fracture on the Earth's surface does things like break apart houses, break apart roads. We went and saw two houses that were completely snapped in half."

The epicentre was about 40km northwest of Christchurch, where stunned locals gathered yesterday to view the damage. A previously straight road had shifted about 3m in one place, while cracks large enough to swallow a person had opened in the ground. Officials have refused to rule out deaths.

Trish Langfield, of Cowra in NSW, was on the 21st floor of her hotel when the earthquake hit. She estimates the building swayed a metre either side.

"It swayed left to right. Extremely," she said.

Jenny Porter, of Sydney, was one of the tourists at Christchurch Airport yesterday, having feared for her life. "It was quite phenomenal," she said. "[We] just didn't know if the house was going to collapse."

New Zealand sits above an area of the Earth's crust where two tectonic plates collide. The country records more than 14,000 earthquakes a year, but only about 150 are powerful enough to be felt above land.

New Zealand's last major earthquake registered 7.8 on the Richter scale and hit the South Island's Fiordland region on July 16, 2009, moving the southern tip of the country 30cm closer to Australia.