New Zealand scientists have rounded on a quasi-mystic mathematician known as the "Moonman" who claims he predicted the devastating Christchurch earthquake by studying the moon.

Ken Ring, the author of books linking the moon with weather patterns, says he accurately forecast the February 22 tremor, which left about 240 people feared dead, in a Valentine's Day tweet.

"Potential earthquake time for the planet between 15th-25th, especially 18th for Christchurch, +/- about 3 days," Ring tweeted on February 14. "Short... and sharp."

Now traumatised residents are fearful after another Ring prediction: that Christchurch -- hit by two major quakes in the past six months, along with thousands of aftershocks -- will suffer another big tremor in the coming days.

"I'm hoping he's wrong, but we're going down to our holiday house for the week just in case," said schoolteacher Kirsty Carruthers. "It'll help take our minds off things, and it can't hurt to get away."

Ring maintains the risk of another quake is high because the moon is now unusually close to the Earth, exerting a strong gravitational pull.

But scientists have scoffed at Ring's claims, with Canterbury University tectonics expert Mark Quigley calling them "ludicrous".

"No one has predicted the recent earthquakes in Canterbury," Quigley said.

"Vague quotes about dates of 'increased' activity plus or minus several days, without magnitudes, locations, and exact times do not constitute prediction.

"(This) is opportunistic and meaningless self-promotion during a time of national crisis."

Matt Gerstenberger, of New Zealand's Institute of Geological and Nuclear Sciences, said: "The correlation is low enough so that a prediction based on (the moon) would be correct only a small proportion of the time, and would be wrong much more often than it is correct."

Systematics expert David Winter ran a statistical analysis of earthquake activity against Ring's total predictions, and said there was little to suggest he was credible.

"Once you see how implausible his methods are you realise you'd need incredible evidence to believe his predictions," he said.

"And once you see his run of false positives you realise that his 'prediction' of last week's earthquake doesn't meet that standard."

earlier related report
New Zealand falls silent for quake victims
Christchurch, New Zealand (AFP) March 1, 2011 - Grieving New Zealanders wept and hugged Tuesday, as the nation fell silent to mark the moment last week when an earthquake tore apart Christchurch and claimed hundreds of lives.

At 12:51 pm (2351 GMT Monday), exactly a week after the 6.3-magnitude quake hit New Zealand's second largest city, silence descended across the country for two minutes and flags flew at half mast.

In Christchurch, exhausted emergency crews from around the world briefly set aside the grim task of combing through the wreckage and bowed their heads in respect.

Prime Minister John Key, who grew up in Christchurch, led the tribute in front of a partially collapsed church, within view of the city's devastated cathedral, where up to 22 people are believed to be buried in the rubble.

At his feet feet lay a collection of stones from some of the city's worst-hit sites, crossed with ferns, New Zealand's national emblem and also a Maori symbol of hope and new life.

"It's very sad, this is an earthquake that's claimed the lives of literally hundreds of people and that's hard to put into words," Key told AFP after the two minutes' silence, which was broken only by the sound of weeping.

"This is a very dark moment for us but it's a moment that we will rebuild from."

But with Christchurch facing a reconstruction bill estimated at up to NZ$16 billion ($12 billion), Finance Minister Bill English warned New Zealand's already struggling economy now faced "close to zero growth".

"It's a different outlook from what we expected six months ago but we'll just have to roll with the punches," he told public radio, admitting "I simply don't know" if the country could avoid dipping into recession.

A 4.0-magnitude aftershock shook the area on Tuesday evening, the US Geological Survey said, with its epicentre 26 kilometres (16 miles) southeast of Christchurch at a depth of 10 kilometres.

The official death toll from the disaster stands at 155 but police on Tuesday said it was likely to climb above 240, up from a previous estimate of more than 200.

"We need to start considering the figure of around 240 but (it's) not locked in stone, because we're still getting information in," district commander Dave Cliff said.

Crowds gathered at countless church services around New Zealand, remembering the violent shake that brought down entire office blocks and tore up roads as it reduced much of central Christchurch to smouldering ruins.

At Wellington Cathedral in the capital, the numbers spilled over onto the building's steps, with many weeping openly.

The parliament of Australia, which rushed to aid Christchurch in the quake's aftermath and on Tuesday confirmed its second death in the disaster, also observed the silent tribute.

Key has promised a major inquiry, saying there were legitimate questions about why office blocks tumbled to the ground in a city with supposedly "quake-proof" building standards, six months after another big tremor.

One of the collapsed buildings housed an English-language school attended mainly by Asian students, scores of whom are missing presumed dead. Key said relatives deserved an explanation about why their loved ones perished.

"Obviously the earthquake was something that's beyond our control (but) we are going to get answers for those families about what's gone wrong," he said.

The rescuers who have scoured the ruins with sniffer dogs and sensitive listening devices around the clock for seven days have admitted there is next to no hope of finding more survivors.

For those toiling in the rubble, Tuesday's emotion-charged tribute was the first opportunity to reflect on the enormity of the tragedy they had witnessed, Cliff said.

"It was a very special time," he told reporters.

Christchurch is also experiencing violent aftershocks, with one measuring 4.3 hitting on Tuesday, creating treacherous conditions for the emergency crews and further jarring the stretched nerves of locals.

The tremors have opened cracks in a cliff overlooking suburban streets and threaten to cause landslips, forcing more residents to flee their homes after New Zealand's worst natural disaster in 80 years.