The tsunami warning has been issued in 27 countries around the Indian Ocean --after two earthquakes measuring 8.6 and 8.3 on the Richter scale occurred just several hours apart from each other in the waters of Indonesia's Aceh province.

 In Vietnam, the Institute of Geophysics is the only agency responsible for releasing tsunami warnings, for monitoring, analyzing and giving warnings when it can see a tsunami risk.

 According to Associate Professor Dr Nguyen Hong Phuong from the Center for Earthquake and Tsunami Warning of the Institute of Geophysics, there has been no official document about the damages caused by tsunamis in Vietnam. As there was no tsunami monitoring system, no information about tsunami has been reported.

 In many cases, tsunamis could be mistaken for the phenomenon of water rise caused by storms or short wavelength waves.

 According to the Bureau of Meteorology and Hydrology and Climate Change, in Vietnam, the studies on the seismic regime in the South China Sea and the conditions of tsunami formation only began 10 years ago. The investigations about the tsunamis in coastal areas of Vietnam have been made based on the historical records or the stories of coastal residents.

 Some documents showed that a tsunami once occurred on the coastal area of Thua Thien-Hue province in September 11, 1904, which damaged 22,207 houses, sank 519 boats and killed 724 people. Tsunamis also once attacked the seaside of Nam Dinh in 1930 and Da Nang in 1964. However, no evidence has been found to confirm or reject the information.

 However, reliable proofs have been found to show that three tsunamis attacked Vietnam in the past. The first one occurred on the Tra Co beach, and had no relation with any earthquake. The second one attacked Dien Chau seaside in a year in late 19th or early 20th century. The third once occurred in Nha Trang in 1923.

 Especially, the assumption of scientists that a tsunami occurred in 1923 in Nha Trang has been fortified by the notes taken by Dr Armand Krempt, the assistant to Dr Alexandre Yersin. The documents showed that tsunami once damaged the stable of the doctor in Nha Trang City which was just 5-6 meters far away from the seaside.

 The phenomenon was believed to relate to the volcanic eruption that caused the 6.1 magnitude earthquake on the island of Hon Tro, Phu Quy Island. Maybe the volcanic eruption at Hon Tro Island generated the tsunami.

 Vietnam had not paid big attention to the studies on tsunamis until the tsunami disaster in South East Asia occurred on December 26, 2004 which then killed 273,000 people. However, to date, according to the Institute for Geophysics, tsunami survey has been carried out in 33 places. The surveys have made Vietnamese scientists believe that Vietnam was once attacked by the tsunamis with the 2-3 meter-high waves.

 Vietnamese scientists believe that the risk of a tsunami is not high in Vietnam, but it really exists. In case tsunamis occur, the biggest suffering areas would be the central region, especially the area from Da Nang City to Quang Ngai province.

AN -TD