Tsunami bomb - NZ's devastating war secret

By Eugene Bingham

Top-secret wartime experiments were conducted off the coast of Auckland to perfect a tidal wave bomb, declassified files reveal.

An Auckland University professor seconded to the Army set off a series of underwater explosions triggering mini-tidal waves at Whangaparaoa in 1944 and 1945.

Professor Thomas Leech's work was considered so significant that United States defence chiefs said that if the project had been completed before the end of the war it could have played a role as effective as that of the atom bomb.

Details of the tsunami bomb, known as Project Seal, are contained in 53-year-old documents released by the Ministry of Foreign Affairs and Trade.

Papers stamped "top secret" show the US and British military were eager for Seal to be developed in the post-war years too. They even considered sending Professor Leech to Bikini Atoll to view the US nuclear tests and see if they had any application to his work.

He did not make the visit, although a member of the US board of assessors of atomic tests, Dr Karl Compton, was sent to New Zealand.

"Dr Compton is impressed with Professor Leech's deductions on the Seal project and is prepared to recommend to the Joint Chiefs of Staff that all technical data from the test relevant to the Seal project should be made available to the New Zealand Government for further study by Professor Leech," said a July 1946 letter from Washington to Wellington.

Professor Leech, who died in his native Australia in 1973, was the university's dean of engineering from 1940 to 1950.

News of his being awarded a CBE in 1947 for research on a weapon led to speculation in newspapers around the world about what was being developed.

Though high-ranking New Zealand and US officers spoke out in support of the research, no details of it were released because the work was on-going.

A former colleague of Professor Leech, Neil Kirton, told the Weekend Herald that the experiments involved laying a pattern of explosives underwater to create a tsunami.

Small-scale explosions were carried out in the Pacific and off Whangaparaoa, which at the time was controlled by the Army.

It is unclear what happened to Project Seal once the final report was forwarded to Wellington Defence Headquarters late in the 1940s.

The bomb was never tested on a full scale, and Mr Kirton doubts that Aucklanders would have noticed the trials.

"Whether it could ever be resurrected ... Under some circumstances I think it could be devastating."

Thanks to

Sydney Morning Herald

Scientists puzzled over quake ripples
March 29, 2005 - 2:54PM

Tsunami experts can't understand why a forceful earthquake off Indonesia overnight failed to produce massive waves similar to those generated by the December 26 quake that killed at least 174,000 people in the same region.

A magnitude 8.7 quake shook Indonesia's west coast, killing hundreds of people and spreading panic another devastating tsunami was on the way.

There was no tsunami, but a small wave was detected by a tide gauge on Cocos Island off Western Australia, about 2,400 kilometres south of the epicentre, according to the Pacific Tsunami Warning Centre on Oahu.

"I'm baffled an earthquake this size didn't trigger a tsunami near the epicentre," said Robert Cessaro, a geophysicist at the centre, operated by the National Oceanic and Atmospheric Administration.

The centre is responsible for monitoring seismic and ocean conditions in the Pacific and alerting Pacific Rim nations and United States agencies.

Centre Director Charles McCreery said earthquakes of at least 8.0 magnitude usually generate major tsunamis.

"We expected some destructive tsunami with some distant destructive effects. It was surprising," he said.

The latest event also demonstrated "there's a whole world of uncertainty about trying to judge a tsunami based on the earthquake data," he said.

The warning centre initially estimated the December 26 earthquake to have a magnitude of 8.0, but it turned out to be larger, with a magnitude of 9.0.

Monday's preliminary estimate was magnitude 8.5 but had no destructive tsunami.

"The one we initially thought was bigger turns out to have no effect," McCreery said. "The one we initially thought was smaller had a huge effect. This is the challenge of tsunami warning."

The warning centre, established in 1949, came under heavy criticism following the December tsunami for not being more aggressive about warning Asian nations and possibly saving thousands of lives.

Earlier this month, a group of 58 European tsunami survivors and relatives of victims sued NOAA and other agencies, alleging the centre did not do enough to warn people about the disaster.

"Although we certainly wish that somehow the event unfolded in a way that we could've done more for the region, we really did all we could under the circumstances," McCreery said.

Since then, several Indian Ocean nations have established communications with the centre and are now on its alert list.

On Monday the facility was able to alert those nations.

The Indian Ocean has no warning centre similar to the one in Hawaii.

2005 AP

Sydney Morning Herald

Why this earthly lightning struck twice

Date: March 30 2005

Two weeks ago an expert warned Sumatra to expect another quake. Yesterday he was proved right. Richard Macey and Deborah Smith report.

It was 2.33am when Mark Leonard's mobile phone rang. The seismologist with Geoscience Australia was woken by a computer-generated message announcing that the west coast of Sumatra had been rocked by another massive earthquake, bringing back horrific memories of the Boxing Day tsunami.

A dismayed Dr Leonard studied the details relayed from automated seismology stations around the country.

The culprit, just as it had been on December 26, was the Indo-Australian tectonic plate that has been steadily forcing its way north at up to seven centimetres a year, for centuries. Where it collides with its neighbouring Eurasian plate, on which the island of Sumatra rides, the Indo-Australian plate is driven deep into the Earth's mantle.

Tremendous forces build up where the opposing plates jam together. The inevitable result is that sooner or later one section, unable to contain the mounting stress, must slip, triggering a powerful earthquake. It happened in one section of this region, known as the Sunda trench, off Sumatra's south coast in 1833. Twenty-eight years later, in 1861, it slipped again, just to the north. Then there was a lull until, on Boxing Day last year, yet another section of the Sunda trench ruptured near the northern tip of Sumatra, creating the tsunami that claimed almost 300,000 lives.

Two weeks ago, John McCloskey, of the University of Ulster, went public with his prediction that the region was a prime target for another major quake - and soon. People tended to think lightning didn't strike twice in the same place, he told the Herald. "But with earthquakes it's exactly the opposite."

His team had calculated that the Boxing Day earthquake had increased stresses in the adjacent area of the Sunda trench, which had not experienced a quake since 1861. At 2.09 yesterday morning, Sydney time, the inevitable happened. The plates ruptured, almost exactly where Professor McCloskey had predicted, triggering a massive 8.7 magnitude earthquake, the world's eighth biggest since 1900.

The Pacific Tsunami Warning Centre, based in Hawaii, was soon beaming out alerts, advising the "evacuation of coasts within 1000 kilometres of the epicentre". Thousands of people were evacuated in Thailand, Sri Lanka and Malaysia.

"At 4am [Sydney time] we were very concerned there would be another tsunami," Dr Leonard said. But as the hours passed there were no reports of coast beyond Sumatra being swamped.

At 4.35am tidal gauges on the Cocos Islands off Western Australian merely noted a wave 25 centimetres high, from peak to trough, passing harmlessly by. Several more waves followed in the next hour. At 8.30am the sea level at Hillarys, about 30 kilometres north of Fremantle, rose from 10 to 20 centimetres, and then settled back.

About the same time, said Dr Leonard, observers in the Maldives, in the Indian Ocean, were reporting that the sea level had risen just 20 to 40 centimetres. Late yesterday, however, news did emerge of a three-metre tsunami wreaking havoc of Simeulue. Nevertheless, as Dr Leonard studied the data, he gradually realised this was no repeat of the Boxing Day calamity, which killed 300,000 people across 11 Indian Ocean nations.

Although the quake had registered 8.7, and was still "a very, very big earthquake" by any measure, it was on the order of eight to 10 times weaker than the magnitude 9 quake that triggered the December 26 tsunami. While the numbers appear close, the force of earthquakes is measured on an exponential scale. The area of crust that shifted was also much smaller - about 50 kilometres wide and 550 kilometres long - compared with the slab of earth 1000 by 250 kilometres that slipped last year. The plate's sideway slip probably averaged only two or three metres, a quarter of the average shift in the Boxing Day rupture.

Last year's quake, noted Dr Leonard, happened on a section of faultline running north to south. The result was a tsunami that rolled out across the Indian Ocean, heading due west, slamming into Sri Lanka, India and finally Africa. The faultline that shifted yesterday runs from the north-west to the south-east, parallel with Sumatra's coast. This time the tsunami headed south-west, out into a largely empty ocean. "This quake was probably due to happen sometime in the next decade," said Mr Leonard, confessing, "I was not expecting another one so soon." He speculated the Boxing Day event had "probably nudged it forward ... it must have been ready to go".

The seismologist declined to punt on what would happen next, saying he did not believe earthquakes could be predicted. "I would not be surprised if there is another 9 magnitude quake off south-western Java ... some time in the next couple of centuries."

Professor McCloskey was not so cautious. "Unfortunately, I'm not at all surprised by today's news," he told ABC radio. He said the next stretch of Sumatra's undersea Sunda trench would now be under additional stress from yesterday's quake. It was too early to say whether this would trigger another quake in the region that has not ruptured since 1833.

He also predicted this quake could increase stress on a faultline running down the centre of Sumatra and under the city of Banda Aceh, already destabilised by the Boxing Day quake.



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