Powerful earthquakes struck Indonesia for a third day on Friday, terrorising thousands of people who were refusing to return to coastal homes in fear of tsunami and falling debris. Seismologists warned that the worst may be yet to come.
Experts have been predicting a repeat of the monster temblor that triggered the 2004 Asian tsunami, killing more than 230 000 people in a dozen nations. American Kerry Sieh, who has spent decades studying the fault along Sumatra island, said the new jolts could be leading up to the big one.
”No one can say whether it will be in 30 seconds or 30 years,” he said, adding that the recent developments made him nervous. ”But my intuition tells me it will be sooner rather than later.”
The 8,4-magnitude quake that shook South-East Asia on Wednesday has been followed by dozens of strong aftershocks that have killed at least 13 people, damaged hundreds of homes and churned up a 3m-high tsunami. Magnitude-7,8 and -7,1 tremors on Thursday were followed by a 6,4 on Friday.
Geologists say the colossal quakes are all on the edge of the Menawai island patch — which has experienced mammoth temblors every two decades, the last in 1833 — and have piled even more pressure on to the fault.
”They are basically like dogs nipping at the heels of the horse,” said Sieh, of the California Institute of Technology. ”If a giant earthquake happened tomorrow, we would say, ‘My God! How much more obvious could it have been?”’
The wall of water that slammed into several fishing villages along Sumatra’s coast on Wednesday swept away nearly a dozen houses, but overall damage was ”minimal”, Indonesian President Susilo Bambang Yudhoyono said after an air-force aerial survey.
A nine-member United Nations assessment team reached the same conclusion after visiting the area, saying that a major international relief operation was not required, John Holmes, the UN’s emergency relief coordinator, said in a statement from New York.
Many people said a public awareness campaign launched after the 2004 tsunami paid off, including warnings issued over mosque speakers and training provided by local officials on how to escape a disaster.
The latest quakes — together with the 9,0-magnitude temblor in 2004 and a 8,7 tremor in early 2005 — deeply concern experts.
Indonesia, the world’s largest archipelago, with a population of 235-million people, is prone to seismic upheaval due to its location on the ”Ring of Fire”, an arc of volcanoes and fault lines encircling the Pacific Basin.
One major fault, which runs the length of the west coast of Sumatra about 200km offshore, is the meeting point of the Eurasian and Pacific tectonic plates, which have been pushing against each other for millions of years. This can cause huge stresses to build up.
”There is a strong indication this foreshadows the big one,” Danny Hillman, an earthquake specialist at the Indonesian Institute of Science, said of this week’s seismic activity. ”We all agree there is an 8,5 or stronger earthquake waiting to happen.” ‒ Sapa-AP