Massive earthquake hits Indonesia, no tsunami risk

Wednesday, April 11, 2012 

An 8.6 magnitude earthquake occurred off the Indonesian coast at 08:38:37 UTC today, causing a tsunami watch to be issued over the entire Indian Ocean.

According to the U.S. Geological Survey, the quake struck at a point 308 miles (495 km) southwest of Banda Aceh, the provincial capital, located on the northern extremity of the country's Sumatra island, at a depth of 20.5 miles (33 km). Local media reports suggest that people in Sumatra fled from their homes and offices in fear. The 8.6 quake was followed by a quake measuring 8.2 on the Richter Scale.

The Pacific Tsunami Warning Center (PTWC) advised authorities to "take appropriate action", stating that they were not aware whether a tsunami had occurred yet. The earthquake, initially believed to be 8.9 on the Richter Scale was later revised to be an 8.7 and finally an 8.6 quake. In reaction to the earthquake, the Indonesian disaster management agency noted that power had been shut down in Aceh. Moreover, people were being warned by sirens of the danger and were going to higher ground. Agency spokesman Sutopo said: "The electricity is down, there are traffic jams to access higher ground. Sirens and Koran recitals from mosques are everywhere."

In its report, the PWTC issued a tsunami watch for 28 countries, including, but not limited to Indonesia, India, Sri Lanka, Australia, Myanmar, Thailand, Maldives, United Kingdom, Malaysia, Mauritius, Singapore, Bangladesh, miscellaneous Indian Ocean islands, Pakistan, Somalia, Oman, Iran, Bangladesh, Kenya, South Africa and Mozambique. They mentioned that "[e]arthquakes of this size have the potential to generate a widespread destructive tsunami that can affect coastlines across the entire Indian Ocean basin."

The tsunami warnings were initially issued for Indonesia after the 8.6 earthquake and later issued for a further two hours after the 8.2 earthquake hit the Aceh province. The watch was lifted for Myanmar, Australia and Malaysia. Later, India too ended its tsunami watch, with a scientist at the Indian tsunami warning center noting that "the danger has passed".

Earlier, the tremors were felt as far away as Bangkok in Thailand and south India, particularly in Bangalore and Chennai. According to locals, people left their buildings in Bangalore on feeling the tremors. The Indian National Centre for Ocean Information Service issued a red high-level warning for the Andaman and Nicobar Islands. The southeastern coasts of Andhra Pradesh and Tamil Nadu were put on lower warnings. According to Sky News, people residing near the coast were asked to move away from the sea in India. The tremors there reached upto the northern city of Kolkata. Kolkata and its surrounding areas felt tremors, also felt in North 24 Parganas and the town of Siliguri in the same state. Several people rushed out of their office as windows and doors rattled due to the quake, while some buildings developed cracks. Metro Rail services were suspended in the city, and people were asked to leave the stations.

Similar warnings were issued by the governments in Sri Lanka, where mild tremors were experienced at Colombo. The tsunami warning was however lifted after 6 p.m. local time. But the government advised people not to go close to the sea. Smith Dhamasoroja, of the National Disaster Warning Foundation, predicted that Thailand would have to face a tsunami as the earthquake was so powerful. Thai Meteorological Department deputy chief Somchai Baimoung however stated that no warning had yet been issued. Later a warning was issued in the country and subsequently lifted. In Bangladesh, two tremors were felt. But the authorities stated there was no fear of a tsunami.

Amy Vaughn of the U.S. Geological Survey told Sky News that because the earthquake was so massive, "a large body of water is disturbed by the movement of the fault". Therefore, since the epicenter was so close to the west coast of Sumatra, "it could be devastating for the region." In Malaysia, high-rise buildings shook for over a minute.

Indonesia straddles the Pacific Ring of Fire, a major earthquake belt. On December 26, 2004 a 9.2-magnitude earthquake in the same area triggered massive tsunami waves, killing almost 220,000 people.

Sources

• Reza Munawir. "Huge quakes off Indonesia stir panic, but no big tsunami" — Reuters, April 11, 2012
• "Indian Ocean tsunami alert lifted after Aceh quake" — BBC News Online, April 11, 2012
• "Tsunami Bulletin Number 001" — Pacific Tsunami Warning Center, April 11, 2012
• Agencies. "Indonesia earthquake: Alert on but disaster panel rules out tsunami in Indian Ocean" — The Indian Express, April 11, 2012
• "Magnitude 8.6 - OFF THE WEST COAST OF NORTHERN SUMATRA" — United States Geological Survey, April 11, 2012
• Associated Press. "Tsunami fears recede after earthquake in Indian Ocean" — The Australian, April 11, 2012
• NewsCore, Angus Thompson. "Geelong man tells of tsunami fears following two huge earthquakes off the Indonesian island of Sumatra" — The Herald Sun, April 11, 2012
• "India ends tsunami alert after Indonesia quakes" — Reuters, April 11, 2012
• R.K. Radhakrishnan. "Mild tremors in Sri Lanka; tsunami warning lifted" — The Hindu, April 11, 2012
• "Tsunami warning after 2 quakes in Indonesia lifted" — IBNLive, April 11, 2012