Indonesia quake adds to fears of more disasters
Indonesia quake adds to fears of more disasters
Stuart Grudgings Reuters/Jakarta
The massive tremor that struck northern Indonesia this week has confirmed experts' fears that a December earthquake set off a domino effect of seismic instability that could last decades and kill thousands.
Seismologists are already sure that Monday's magnitude 8.7 quake off Sumatra island was a direct result of raised stress levels in the earth's crust caused by the Dec. 26 tremor.
And they say there is now a heightened risk of further large quakes -- not just aftershocks -- in the area, although predicting them accurately remains impossible.
"Unfortunately that is a real possibility -- the world works that way," Professor John McCloskey, head of environmental sciences at the University of Ulster, told Reuters by telephone.
"Earthquakes tend to trigger each other so one earthquake is followed by others."
In a report published in mid-March that proved chillingly accurate, McCloskey's research team said the magnitude 9.0 December quake, which left nearly 300,000 people dead or missing around the Indian Ocean, had significantly raised stress levels in the Sunda trench near the west coast of Sumatra island.
Less than two weeks later, the world's seventh most powerful quake in the last 100 years struck along the trench, killing as many as 2,000 people on tiny Nias island and surrounding areas.
It did not trigger a tsunami, unlike the December quake and previous earthquakes on the Sunda trench in 1833 and 1861.
In the March report, McCloskey's team also said the Dec. 26 quake had raised stress levels even more substantially along the Sumatra fault near the city of Banda Aceh, which bore the brunt of the tsunami.
"I'm not saying the domino effect will happen in that way but there are good physical reasons why that domino type of effect can happen," said McCloskey.
"And it would not be wise to assume: that's the second big earthquake, let's forget about it now. This is an active area ... it's been like this for probably millions of years."
Turkey Comparison
Both of the earthquakes were caused by the Australian tectonic plate grinding under the Indonesian plate, which affects a zone running for around 4,500 km (2,800 miles) stretching from Myanmar down to Indonesia's Java island.
Seismologists are now looking at the experience of Turkey for clues to what might happen in Asia. That country, situated where the Arabian and African plates clash with the Eurasian plate, was hit by 11 major earthquakes last century, the latest a 7.4 magnitude tremor in Izmit in 1999 that killed more than 30,000.
"It's a risk. It does happen ... it's happened in Turkey and Japan, but it doesn't always happen so it's difficult to say," said Phil Cummins, a seismologist at GeoScience Australia.
"Certainly there's increased risk and we need to exercise caution in the future."
Each point on the scale measuring earthquakes represents a 30- fold increase in energy, but a quake's destructiveness also depends on the depth of its epicentre, the population concentration and people's preparedness.
McCloskey said the increased risk of quakes in Southeast Asia raised the importance of educating people about proper building techniques and safety drills.
"It's a real live issue when people are rebuilding," said McCloskey.
"If you allow cowboys to build, people will die as a result." But deep poverty and lack of education in areas like northern Indonesia mean earthquakes will inevitably prove more destructive than in richer countries.
Triman Zega, an 18-year-old gardener on Nias island said he has never had any training on how to respond to an earthquake.
"The best thing is to follow my instinct -- run," he told Reuters. (Additional reporting by Tomi Soetjipto in Nias)
(Editing by Dan Eaton; Reuters Messaging: daniel.eaton.reuters.com@reuters.net; +6221 384 6364)) REUTERS
GetRTR 3.00 -- APR 1, 2005 13:30:06