The Indonesian and Thailand coasts of the Indian Ocean seem to have experienced tragedies like the 2004 enormous tsunami wave that killed in the hundreds of thousands more often than one might believe. Even more than that, this phenomenon could happen regularly, at a rate of 600 years, as the latest studies show. According to the research, a similar catastrophic event took place about 600 years ago, flooding the inland portions of the region.

 

The disaster of 4 years back was caused by an extremely powerful earthquake of 9.2 degrees on the Richter scale, which tore apart the Sunda Trench the 1,500 km (900 mile)-long fault of the northeastern part of the Indian Ocean. The aftermath of the calamity reported over 220,000 dead in more than 10 countries. The possibility of such an event repeating any time soon has led two teams of researchers to seek for clues of previous similar occurrences.

 

One team scoured the sandy coasts of Indonesia, while the other did the same in Thailand, hoping to come across preserved fossil clues that would indicate previous tsunami activity. They drilled for the clues in the long trenches between the coastal marsh-filled ridges, and found them well-preserved in the sedimented layers of sand. The Indonesian team found the site of the happening about 2 km inland, to the north of the Meulaboh town in northern Sumatra, where waves of 35 meters (113 feet) were reported in 2004.

 

The Thailand site was discovered on the Phra Thong Island, 124 km (77 miles) north of Phuket, which registered waves as high as 20 meters (65 feet) during the 2004 tsunami. The organic remains discovered were carbon-dated to 1290-1400 AD (Indonesia), and 1300-1450 AD (Thailand). The Indonesian team discovered even older clues leading to the possibility of a disaster, resembling in proportions, taking place around 780-800 AD (Thailand findings were too scarce to count as solid evidence), while the Thailand group found tsunami remains about 2,200 years old.

 

This could mean that there is a period of about 600 years for the Sunda Trench to accumulate enough stress to provoke a catastrophe of such proportions. “Inhabitants might consider the benefits of living close to the sea as greater than the risks of a catastrophic tsunami that will not return for many generations,” shared Norwegian geologist Stein Bondevik. “Also, it does not make sense to invest in and maintain a warning system for devastating tsunamis if they recur so infrequently. But smaller tsunamis may well happen more often, and a warning system could save lives during such event,” he added.