Thursday, October 29, 2009


Jakarta, Oct. 29, 2009 (ANTARA) - First Lady Ani Yudhoyono has reminded the people that due to its geography, Indonesia is vulnerable to disasters and therefore they must be prepared for that.

"We must become used to it and always be alert," she said here on Wednesday when officially opening a Women`s International Club (WIC) charity bazaar.

The warning is necessary as Indonesia sits on the Pacific "Ring of Fire," the edge of a tectonic plate which is prone to seismic upheavals.

On Sunday (Oct. 25) alone, for instance, six earthquakes with magnitudes ranging from 5.0 to 6.1, hit Indonesia.

Indonesia has been rocked by powerful earthquakes over the past few years especially. The latest was a 7.9-magnitude earthquake which devastated West Sumatra, on September 30, 2009, killing 1,117 people, injuring thousands of others, and destroying at least 88,272 houses.

Another powerful earthquake affecting Indonesia was the temblor that rocked Yogyakarta and some parts of Central Java Province, in May 2006, killing 5,782 people, injuring 36,299 others and damaging 135,000 houses.

The most powerful one in recent years was a 8.9-magnitude earthquake which triggered a gigantic and deadly tsunami in Aceh Province and Nias Island (North Sumatra Province), which left around 200,000 people dead or missing and around one million other homeless, in December 2004.

A scary prediction was recently made by Kerry Sieh, director of the Earth Observatory of Singapore, who said that a colossal earthquake may hit Indonesia`s Sumatra island within the next 30 years, triggering a tsunami and making last September 30`s deadly temblor look tiny by comparison, AFP reported.

"We expect it will be about a magnitude 8.8, plus or minus say 0.1," Sieh, an American professor, said at a presentation recently at the Nanyang Technological University, where the observatory is located.

Based on historical earthquake trends from geological analyses of coral specimens from the region, last month`s quake was just a precursor, Sieh said.

Likening the pressures under the affected fault to a coiled spring, Sieh said the recent quake "had really very little effect in terms of relieving the spring" which will unleash pent-up energy possibly within the next 30 years.

Agreeing with the 8.8-magnitude earthquake prediction, Danny Hilman Natawidjaja, a geologist from the Indonesian Institute of Science, said pressure had created fault lines around Padang, the capital of West Sumatra, during the series of earthquakes off the Sumatran coast in the last few years.

"The 7.9-magnitude earthquake at 5.16pm on Sept 30 that shook Padang could not be categorised as large-scale. We are talking about the possibility of an earthquake of over 8.0 on the Richter scale, a megacrush accompanied by a tsunami," he said in a statement issued by the institute.

Danny who has been studying the Mentawai fault zone off the coast of Sumatra for 12 years together with fellow researcher Prof Kerry Sieh from the Nanyang Technology University (NTU), Singapore, believed that the built-up pressure could cause a 8.8-magnitude earthquake.

"Theoretically, I can say that this major earthquake may happen tomorrow, the day after, next month or next year. At the latest, it may occur in the next 10 years."

Coming to a similar conclusion, Sri Widiyantoro, an Australian-trained geophysicist from the Bandung Institute of Technology, said recently that the West Sumatra quake had done little, if anything, to relieve the immense pressure building up kilometres below the surface as the Indo-Australian and Eurasian tectonic plates grind against each other.

"We had all been expecting one in West Sumatra, and when the earthquake happened last week, we all thought `OK, this is the one we had been anticipating`,`` said Sri Widiyantoro. ``But now we have had a close look at it, we now know that it wasn`t.``

The Indo-Australia tectonic plate smashes into the Eurasian plate about 200 kilometres off the coast of Sumatra.

For almost 200 years, the pressure has built up to extraordinary levels in this so-called subduction zone. The first release of tension was the magnitude 9.1 undersea quake in 2004 off Aceh on the northern tip of Sumatra, when a portion of the Indo-Australian plate cracked and slipped 30 metres across a 1000-kilometre front.

Months later, an 8.7 magnitude quake occurred further south in Nias, while there was a quake in 2007 off the coast of Bengkulu in South Sumatra.

"The series of events left a gap in West Sumatra,`` said Dr Widiyantoro. "It seems that this [250-kilometre-long] segment has not been broken."

It is inevitable in coming decades that it will be broken, perhaps in the near future given the events along the collision zone.

Dr Widiyantoro and his team found this after examining GPS imagery of the area, which shows the Indo-Australian plate hasn`t moved.

"So we are still wondering whether a much bigger earthquake could occur," he said. "What we don`t know is whether it will all break at once or whether there will be several smaller events."

Since reports on the colossal earthquake prediction were made public, rumors on huge earthquakes were circulated in several regions, including Bengkulu, West Java and Jakarta.

News of the impending 8.5-magnitude earthquake widely spread throughout Jakarta via SMS and Twitter, with the rumor rife about the Indonesian capital with a population of about 12 million also to be hit by an earthquake on October 24, 2009.

However, this was immediately refuted by the Indonesian Agency for Meteorology, Climatology and Geophysics (BMKG) and it turned out to be false.

"The rumors are unfounded and BMKG has never made such a prediction," BMKG chief Dr. Eng. Sri Woro B. Harijono said in a press statement received by ANTARA recently.

Up to now, scientists have yet to gain the capability of predicting a tectonic earthquake, she said.

The then Research and Technology Minister Kusmayanto Kadiman also tried to calm down the people recently by explaining that an earthquake could not be predicted before it happened and up to now no scientist could tell when a temblor would occur.

The former minister emphasized the need to have quake-proof building construction standards, especially in quake-prone areas such as Padang and Aceh (Sumatra Island), and Banten (western Java).

Earlier, on October 2, when visiting quake-devastated West Sumatra, President Susilo Bambang Yudhoyono suggested that a feasibility standard rule for building construction should be formulated and applied in the construction of storeyed buildings in earthquake- and other disaster-prone regions.

"A tight regulation must be introduced, whether a government regulation or a regional government regulation, or bylaw. We have here now the minister/state secretary and the cabinet secretary. They should together with the minister of public works and the minister of housing issue a certification rule on the requirements for storeyed buildings in quake prone areas," President Yudhoyono said.

According to the president, many storeyed public buildings such as shopping centers, schools and government buildings are always full of people.

"One can imagine if such a building is not strong, does not pass a test and is not strong against an earthquake. Therefore, buildings must be subject to accountable certification," he said.

The president said the rule on the feasibility of a storeyed building would be issued and should be effective throughout Indonesia, particularly in quake-prone areas.

Earthquakes don`t kill people, but collapsing buildings do. ***3***


2. 17:20.

(T.F001/A/F001/B003) 29-10-2009 20:38:24

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