The tsunami that killed 230,000 people in 2004 was the biggest in the Indian Ocean in some 600 years, two new geological studies suggest.

tsunamiimgnamkhem-01That long gap might explain how enough geological stress built up to power the huge undersea earthquake that launched the killer waves four years ago, researchers said.

The work appears in Thursday’s issue of the journal Nature. Two research teams report that by digging pits and taking core samples in Thailand and northern Sumatra, they found evidence that the previous comparably large tsunami struck between the years 1300 and 1400.

The researchers found deposits of sand that were apparently left by the waves, and estimated their age with carbon dating of associated plant debris.

The December, 2004, disaster killed people in 14 countries. Waves more than 30 metres tall struck northern Sumatra and deposited sand more than 1.5 kilometres inland, researchers said.

In Thailand, the waves also ran that far inland and left deposits of sand some five to 20 centimetres thick.

The 26 December tsunami was the worst natural disaster to ever strike Thailand, causing loss of life as well as major damage to property, the environment and the economy. The severe impact on the natural environment in turn had serious consequences on the fishing and tourism industries and, therefore, thousands of families’ livelihoods.

Description
Figure
No. people killed5,395
Bodies still unidentified1,650
Children orphaned
(loss of one or both parents)
1,480
Fishing boats destroyed or damaged7,500
Houses destroyed or badly damaged4,806
Thai Government assistance /compensation
(as of 01 September 2005)
1.06 billion USD
(inc. budget contributions, Prime Minister’s Office, bank credit)
UN emergency phase relief assistance2.6 million USD

Source: UN