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power24
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http://news.bbc.co.uk/1/hi/sci/tech/4354217.stm
New Asian quake threat warning
The quake occurred at the boundary of the Indian and Burma plates. A build-up of stress on faults in Sumatra following the Indonesian earthquake is likely to trigger another large quake and perhaps a tsunami. That is the claim made in Nature by a team from the University of Ulster.
The slip that caused last year's devastating quake placed increased stress on the Sumatran fault and on the adjacent undersea Sunda Trench.
A new rupture could trigger a magnitude 7-7.5 quake on land and a magnitude 8-8.5 quake beneath the sea, they say.
"I am comfortable talking about a significant increase in the risk of another quake"
John McCloskey, University of Ulster
The 2004 earthquake occurred when the deep, flat Indian plate slipped under the Burma plate.
Major earthquakes tend to cluster in these subduction zones where two or more plates of the Earth's crust grind and overlap.
When a quake takes place, the displacement causes the surrounding crust to become distorted. This places stress on other fault lines and structures in the area.
Researchers from the University of Ulster at Coleraine used information about displacement following December's magnitude 9.0 quake to calculate the stresses it placed on the surrounding region.
They concentrated on the Sumatran fault, a so-called "strike-slip" fault which cuts through the island of Sumatra, and the Sunda trench, a continuation of the underwater subduction zone that ruptured to cause the tsunami last year.
"We found that both of them had been significantly loaded, in stress terms, by the 26 December quake," said lead author John McCloskey.
Their results show a stress increase of up to five bars in the 50km stretch of the Sunda trench located next to the rupture zone. They show an increase of up to nine bars for about 300km on the Sumatra fault near the city of Banda Aceh.
Based on these findings, the scientists predict a possible magnitude 7-7.5 earthquake on the Sumatran fault and a magnitude 8-8.5 quake at the Sunda trench.
"The huge changes in stress mean that I am comfortable talking about a significant increase in the risk of another quake. But that is as far as I am prepared to go," Professor McCloskey told the BBC News website.
The researchers stop short of predicting when another large quake will strike the region. But similar events elsewhere in the world have occurred within a few years of each other, or even a few months.
Another tsunami?
In Japan, at least five major quakes in the Nankaido segment of the Nankai subduction zone have been accompanied by similar events on the linked Toanakai/Tokai segment within five years - and three of the subsequent quakes ruptured in the same years as their precursors.
The magnitude 7.4 Izmit earthquake in Turkey in 1999 triggered the magnitude 7.1 Duzce earthquake three months later.
Some researchers believe large earthquakes occur at the Sunda trench on a cycle of 200 years, which is determined by stress loading at the subduction zone. The last big event occurred 150 years ago, but Professor McCloskey said the recent quake could have accelerated this cycle.
"The amount of extra stress could be equivalent to 50 or 60 years of loading. But I personally am not convinced by this theory," he said.
A large earthquake at the undersea Sunda trench had the potential to cause another tsunami, the University of Ulster researcher added.
But Professor Nick Ambraseys of Imperial College warned against making predictions that could cause panic, when there was no way to tell when another earthquake would occur.
"False alarms and inaccurate timing could create more problems than already exist," he said.
"There is nothing in their article that enables, with any degree of certainty, the prediction of the immediacy of the next earthquake."
The authors of the report say this makes a tsunami early warning system for the Indian Ocean all the more urgent.
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Thai Girls : Meet Sexy Thai Girls
Posted on: 4:51 pm on Mar. 16, 2005
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power24
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Great link Gyaos. The key point for me was how the sumatra fault and sunda trench have been adjusted following the tectonic events of boxing day and how it seems to have changed the vulnerability of this area to subsequent quakes. I know that earthquakes of significant magnitude occur all around the world on a daily basis but the these faults appear to be more prone to subduction and therefore more likely to cause tsunamis.
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Thai Girls : Meet Sexy Thai Girls
Posted on: 4:44 am on Mar. 17, 2005
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power24
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Note that an earthquake of 8.5 on the richter scale has just hit western sumatra. I dont know if this will cause a tsunami but Id recommend keeping an eye out to sea if your in any western Thai coast.
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Bangkok Girls : Meet Sexy Bangkok Girls
Posted on: 12:35 pm on Mar. 28, 2005
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Bangkoksexydotcom
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It is stronger the last time.My dad felt in KL house were shaking nothing here in BKK.
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Thai Women : Meet Matured Thai Women
Posted on: 12:38 pm on Mar. 28, 2005
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thunder368
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just seeen it in the bbc news here in the uk this is not what they need now after 3 months just hope it does not harm any1 even my exgirlfriend who lives out in phucket.was any1 there when it went off and can tell us how every1 is feeling after the quake.i was in pattaya last boxing day and even the girls there would not go out on boats asa they thought another 1 was coming at anytime.even though I could do nothing there I gave every night they came out collecting for the relief fund must of hande over about 150pounds.
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Bangkok Women : Meet Beautiful Thai Girls
Posted on: 2:59 pm on Mar. 28, 2005
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Roger Ramjet
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It was definitely felt in Bangkok last night in the high rise buildings. My apartment block was shaking and all of the Japanese residents ran out! I turned on the TV to see if there was anything on the news - CNN started reporting it about 30 minutes later. The Thai TV channels started covering it about 20 minutes after that.
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Bangkok Girls : Meet Attractive Thai Girls
Posted on: 7:37 pm on Mar. 28, 2005
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MarkC
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Quote: from Roger Ramjet on 7:31 am on Mar. 29, 2005
It was definitely felt in Bangkok last night in the high rise buildings. My apartment block was shaking and all of the Japanese residents ran out! I turned on the TV to see if there was anything on the news - CNN started reporting it about 30 minutes later. The Thai TV channels started covering it about 20 minutes after that.
It was almost live on one Thai phone-in show on the wireless in my taxi last night...
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Thai Women : Meet Matured Thai Women
Posted on: 8:41 am on Mar. 29, 2005
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power24
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It seems like John McCloskey (Geophysicist from University of Ulster) from my initial post (two weeks ago) got this one mostly right and now is predicting the possibility of a third larger quake. Again, makes for an interesting read - this time from skynews:
MASSIVE QUAKE PREDICTED
An expert has warned that the latest quake off Sumatra made another massive earthquake in the region more likely.
Professor John McCloskey predicted in the wake of the Boxing Day earthquake and tsunami that there was a likelihood of two more quakes in the region.
Ominously he warned that the latest quake was likely to have added to the stresses on the earth's crust at the second site he was worried about and make a third massive quake a reality.
The University of Ulster based Geophysics expert, who studies earthquake dynamics said: "The location of the latest quake is exactly were we warned it would be.
"We said there were two locations off Sumatra where the stresses had been increased by the Boxing Day earthquake and were likely to indicate another earthquake."
The fault line for the other site "runs right through the city of Banda Aceh" on the northern tip of Sumatra, he said.
The study of data would detail whether he was right.
"We will be doing comparisons of stress levels over the next 12 hours," he said.
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Bangkok Girls : Meet Attractive Thai Girls
Posted on: 11:02 am on Mar. 29, 2005
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