Chandigarh, December 27
There is no historic record of a tsunami in the Indian Ocean; the only earlier reference to a tsunami was in relation to the 1941 Andaman Island earthquake and prior to that in 1880s. That too is not documented, it is, therefore, unfair to say that the tragedy could have been minimised by precautionary steps.
"It is wrong to say that India got caught unawares because there was no record of this natural calamity ever, but now it will automatically get listed into the National Forum for Natural Disasters", Prof Ravinder Kumar of the Centre of Advance Studies in Geology, Panjab University, told The Tribune.
Prof Kumar said that the only precaution one could take in case of tsunami was to have a quick response system whereby the people living in coastal areas could be alerted, "as there is about half an hour time between the earthquake and high tides hit the coats". There is a system for tycoons etc existing in states on the coast like Andhra Pradesh. But tsunami is most infrequent and it is almost impossible to predict as compared to a normal earthquake. "All that can be said at the moment is that there is a possibility of aftershocks over the next 24 hours, but these will not be of the same magnitude". He said that unlike earthquakes that could be predicted, tsunami was difficult to foretell.
"For those studying seismic tectonics at the National Geographical Institute, Hyderabad, or people like Harsh Gupta, Secretary at the Department of Ocean Science, a major earthquake in northern India anytime over the next two or three decades is a possibility keeping in mind various factors". He explains that the tip of the Sumatra belt where the tsunami struck extends all the way to Andaman and Nicobar Islands and the earthquake-prone zone extends all the way from the mountains of eastern India up to Arunachal Pradesh further extending into the Himalayas.
The entire belt is genetically linked making the entire region prone to seismic activity. The plate of the Indian Ocean and the Indian peninsula extends to Tibet, Eurasia and is under tremendous pressure that may result in an earthquake higher than 6 on the Richter scale, according to him.
He further explained that tsunami (pronounced tsoo-nah-mee) was a Japanese word, which means, "harbour wave." Tsu means harbour and nami stands for wave. Tsunamis are large waves that are generated when the sea floor is deformed by seismic activity, vertically displacing the overlying water in the ocean. The earthquake, which had its epicentre 257 km south-southwest of Banda Aceh, Sumatra, measured 8.9 on the Richter scale making it the most powerful in the world in the past 40 years. Most of the destruction was caused by seismic waves or tsunami that hit India, Sri Lanka, Malaysia and Thailand within two hours of the first impact of the quake.
The earthquake was the world's fifth most powerful since 1900 and the strongest since a 9.2 temblor slammed Alaska in 1964, U.S. earthquake. Quoting reports he said, "the quake occurred at a place where several massive geological plates push against each other with massive force. The survey said a 1,000 km (620-mile) section along the boundary of the plates shifted, motion that triggered the sudden displacement, causing the huge tsunamis". He said that the tsunami could be several metres high when it hit the shore. Tsunami, he said, was not one giant wave, but a series of waves that come ashore in a short interval.
India has experienced some of the world's most devastating earthquakes. Some 19,000 people died in Kangra district, north-eastern Himachal Pradesh, in April 1905, and more than 30,000 died in Maharashtra and Andhra Pradesh in September, 1993. Although resulting in less extensive loss of life, major earthquakes occurred in Assam in 1950 (more than 1,500 killed) and in Uttarkashi district, Uttar Pradesh, in 1991 (1,600 killed).
India is not a member of the National Oceanic and Atmospheric Administration that forewarns countries of impending disaster. With 6000 km of coast, India would now perhaps become associated with one of the international warning groups to remain abreast of tsunamigenic earthquakes that mainly occur in the Andaman sea, area about 400-500 km south southwest of Sri Lanka and in the Arabian Sea, about 70-100 km south of Pakistan Coast - off Karachi and Baluchistan, experts say.
