A quake measuring 4.8 in magnitude struck Houaphan Province in Laos at 11.26 pm on November 12, at a depth of about 10 kilometres, according to the Earthquake and Tsunami Warning Centre under the Institute of Earth Sciences. The epicentre was around 5 kilometres from the Vietnamese border and the event was assessed as level-one disaster risk, the lowest on the national scale.
Around 11.30 pm, residents in a number of high-rise apartment buildings in Hanoi and nearby provinces such as Son La, Phu Tho and Thanh Hoa reported feeling clear shaking and suspected an earthquake had occurred.
Nguyen Thi Hoai, who lives in Xuan Phuong Ward in Hanoi, said her house is at ground level rather than in a tower block yet she still felt noticeable tremors.
‘The furniture in the house, like the bed and wall-mounted mirror, all shook,’ she said, adding: ‘It is likely there has just been an earthquake near Hanoi.’
The Earthquake and Tsunami Warning Centre said it was continuing to monitor the event.
Earthquakes are occasionally recorded in Hanoi, but they are usually minor and rarely cause damage. Residents most often notice tremors in high-rise buildings.
The most recent notable tremor before this one occurred at 5.46 pm on August 26, when a 3.6-magnitude quake was recorded in Cao Duong Commune, Phu Tho Province. At that time, some people in Hanoi also reported feeling a brief, mild shaking.
From the beginning of the year to the end of July, the Institute of Geophysics recorded 209 earthquakes on Vietnamese territory and in the country’s waters, 20 of them with magnitudes above 3.5.
Experts said that, alongside reservoir-triggered quakes clustered around hydropower dams in Kon Tum Province and Danang City, there are also natural earthquakes. These natural events occur on several fault zones and follow a general pattern, where quakes happen once enough energy has built up. The larger the earthquake, they noted, the less frequently it is likely to recur.
