A Vietnamese science institute said it was finalising a distant early warning system to protect the nation’s 3,000 kilometres of coastline from tsunamis caused by earthquakes in the East Sea.
Nguyen Ngoc Thuy, director of National Institute of Global Physics (IGP), said his organisation was finalising the network for quakes of over 6.5 on the Richter scale, to be submitted to government in August for approval.
Associate Professor Pham Van Thuc, who has long been studying earthquake impacts in the East Sea, said that it would take a tsunami 2 hours 12 minutes to reach the shores of Nha Trang, and 5 hours 30 minutes to reach the Red River Delta in the north.
A source from IGP said that Vietnam’s location at the South East flank of Asia continent was exposed to an average risk of in terms of earthquakes.
But the risk of quakes in Vietnamese waters is about one-twentieth of that in the East Sea.
A previous study by Vietnamese scientists also confirmed that the lack of fault lines in the Vietnam seabed is unlikely to cause tsunamis.
In the past century, there were only three earthquakes in Vietnam, the most recent of which was in 2005.
A series of 4.5-5.1 Richter scale quakes took place in August, October and November offshore southern coastal provinces of Vung Tau and Phan Thiet, shaking buildings and causing panic in HCM City.
Scientists also warned that human’s activities like petroleum exploiting, injecting fluid into deep wells, in limited circumstances, may also spark quake activity.
The main source of earthquakes in the East Sea stems from some geologic faults in the West of Philippines, far from Vietnam’s shores.
Earthquakes in these faults happen at the rate: from 5-5.5 Richter scale on every 3 years, 5.5-6 for every 7 years, 6-6.5 for every 20 years and above 6.5 on every 60 years.
The maximum magnitude of earthquake in the East Sea is predicted at 7 Richter scale.
Though there has been no record of tsunamis caused by these faults, Vietnam remains cautious of the risk to its massive shoreline.
A study by IGP at 33 places along the seashore of Vietnam said that storms can cause waves as high as 10 m, but average at about 5-8 m, capable of damaging dykes and destroying houses.
Several tsunamis have been recorded over the last century due to volcanoes and inclement weather offshore of Vietnam and Philippines, but the risk of recurrence is unlikely.