VietNamNet Bridge – Four earthquakes, measuring from 2.7 to 3.5 on the Richter scale, hit Bac Tra My and Nam Tra My districts in the central province of Quang Nam on Thursday morning (July 26), but no damage or casualties were reported.

Dam of the Sông Tranh 2 Hydro-power Plant in Bac Tra My District. Four quakes hit the two districts of Nam Tra My and Bac Tra My on July 26. — VNS Photo Cong Thanh

Local residents living in the districts heard loud noises and felt the ground shake early in the morning.

However, these tremors did not destroy buildings or houses in the area.

A report from the Earthquake and Tsunami Warning Centre under the Institute of Geophysics, said the four quakes had a seismic focus at a depth from 4.7km to 12.2km.

The institute also said the biggest 3.5-Richer scale tremor occurred in Nam Tra My District – 50km from the Song Tranh 2 Hydro-power Plant – at a depth of 4.7km.

Experts from the institute said that the tremors occurring in mountainous districts of Quang Nam Province, near the hydro-power plant, were caused by water stored in the hydropower plant reservoir.

They said these quakes were not greater than the reservoir’s capacity to withstand quakes of up to 5.5 in magnitude.

The two districts, south of Tam Ky City in Quang Nam Province, have been hit by five quakes ranging from 3.2 to 3.9 on the Richter scale between March of 2017 and June of 2018.

Bac Tra My District, few kilometres to the hydro-power plant, had been stricken by more than 20 earthquakes and tremors since 2012.

The biggest quake, measuring 4.7 on the Richter scale, struck the district in 2012, and was the biggest quake in Quang Nam Province, causing superficial damage to more than 100 houses.

Source: VNS