The risk of tsunami earthquakes affects Vietnam

After the wave propagation effect caused shock last night in some northern provinces and in Hanoi, many people are concerned about the risk of earthquakes and tsunamis affecting Vietnam.

Dr. Le Huy Minh, director of the center for earthquake and tsunami warning, and Dr. Nguyen Hong Phuong, the deputy director of the center, had an article about the risk of tsunami earthquakes in Vietnam.

Risk of earthquake

Vietnam is located in the Southeast of the Eurasian Plate, between the Indian Plate, the Philippine Plate and the Australian Plate. Vietnam territory is not located at the edge of the array so it is less vulnerable to earthquakes than other countries in the region such as Indonesia, Philippines, Malaysia.

But in the territory and territorial waters of Vietnam, there exist complex faults system such as Lai Chau - Dien Bien fault zone, Song Ma fault, Son La fault, Song Hong fault zone, Song Ca fault zone. . so earthquakes often happen.

Distribution of seismic earthquakes in Vietnamese territory and adjacent areas
(Data 1903-2009). Photo: vast.ac.

From the beginning of the 20th century up to now in the Northern region, there are 2 magnitude 8-9 earthquakes (large 6.7-6.8 Richter scale), dozens of level 7 earthquakes (5.1-5.5 degrees Richter) and hundreds of weaker earthquakes. Typically, the earthquake in Dien Bien in 1935 was 6.75 Richter occurred in the Song Ma fault zone.

More recently, the Dien Bien earthquake of 2001 has 5.3 Richter scale with the center of Laos, about 20 km from Dien Bien city, causing damage from mild to collapse more than 2,000 houses in Dien Bien city area.

Earthquake source areas that cause tsunamis can affect coastal areas
and Vietnamese islands. Photo: vast.ac.

From 2007 up to now, many earthquakes with intensity less than 5.5 degrees Ricther occur in Vietnam. The small earthquakes that occurred after the earthquake in Dien Bien did not cause human and property damage, but also showed that the Earth's crust in Vietnam is not completely stable , earthquakes need to be monitored. and research to have a more complete assessment of seismic activity in Vietnam.

Risk of tsunami

So far, there is no conclusive evidence to confirm that tsunamis have affected the coast of Vietnam . However, according to the research results that have been carried out at the Institute of Geophysics, earthquake source areas in the East and neighboring sea areas can cause tsunamis affecting the Vietnam coast region like Riukiu, Taiwan, Manila submerged zone, Sulu Sea.

The time of tsunami propagation from the zone area submerges Manila to the region
Vietnam coast. Photo: vast.ac.

According to calculations of the Ministry of Natural Resources and Environment, if an earthquake of magnitude 8.3 in the Richter area occurs in the Manila deep water trench, it can create a 6.2 m high tsunami in Quang Ngai and 2, 1 m in Nha Trang.

An earthquake with magnitude of 9.2 on the Richter scale in the same area can create a 10.6 m high tsunami in Quang Ngai and 5 m in Nha Trang, and the tsunami time from the deep-water Manila trench to Vietnam coast area after about 2 hours.

Scientifically, earthquakes with magnitudes greater than 6.5 on the Richter scale in sea areas are likely to cause tsunamis, thus the risk of tsunamis in the Vietnamese coast is present and needs to be be interested.