Two powerful earthquakes struck more than 320km (200 miles) off the coast of the Indonesian island of Sumatra yesterday, spreading panic among residents and reviving memories of the devastating 2004 earthquake and tsunami in the same area.
There were no reports of casualties or significant damage, and tsunami warnings were called off hours after they were widely broadcast on television, mobile phones and the internet. The first quake, measured at 8.6 by the US Geological Survey, was felt across a large area. In addition to Indonesia, tremors were felt in Bangladesh, India, Malaysia, Singapore and Thailand. In what ultimately amounted to a test of the region’s tsunami warning systems, residents fled coastal areas for higher ground. In Banda Aceh, at the northern tip of Sumatra, the hurried, spontaneous evacuation came after several minutes of heavy shaking.
The earthquake knocked out electricity and tied up cellular phone services, according to Edo Iskandar (56), a driver who said he was drinking coffee at an outdoor restaurant when the earthquake struck in mid-afternoon. “People started running out into the street,” he said. “All the people at the food stall, people from shops, houses, everybody was in the street panicking, running and looking for higher ground.”
Television footage showed patients wheeled from hospitals on gurneys and traffic-clogged streets in one direction – away from the sea. The tsunami siren sounded, Mr Iskandar said.
In southern Thailand, one witness described a more orderly move to tsunami shelters. “The evacuation went well, as planned,” said Mitree Jongkraijak, the head of a tsunami response team in Baan Nam Khem, a village destroyed by the 2004 tsunami. “All of the volunteers were at their stations,” he told a Thai television station.
The 2004 tsunami, caused by a giant 9.1-magnitude earthquake, killed 230,000 people in more than a dozen countries. Yesterday’s earthquakes were further away from Sumatra and seismologists said the horizontal motion of the first quake made it less likely to trigger a large tsunami. A second quake measured 8.2, the largest of many aftershocks.
Indonesia’s president, Susilo Bambang Yudhoyono, told reporters in Jakarta that the earthquake had caused “a little bit of panic”. The initial quake struck at a depth of 22km (14 miles) with an epicentre 432km (269 miles) southwest of Banda Aceh, according to the US Geological Survey. The strongest aftershock was measured at a depth of 16km (10 miles).
Bruce Pressgrave, a geophysicist with the survey, said the first earthquake was believed to have come from a “strike-slip fault”, which would reduce the likelihood of a destructive tsunami. The wall of such faults moves horizontally with little vertical motion, he told a BBC news programme.
“Since the motion is horizontal, it is not moving the water column; it is less likely to produce a destructive tsunami,” he said.
On the Andaman and Nicobar islands, the closest Indian territory to the earthquake’s epicentre, officials and hotel managers said they felt the earth move at 2.15pm, but said there was no sign of a tsunami or big waves two hours later.
Cmdr Bindu Prakash, an officer with the Indian navy based on the islands, said there had been no noticeable rise in sea levels even past the time the tsunami was supposed to hit the islands. He said the warning was still in effect as a precaution. Deepika Mandal, an employee at the Fortune Resort Bay Island hotel in Port Blair, reported nothing unusual. The sea was "absolutely calm", he said. – (New York Times service)