According to the Institute of Earth Sciences, the tremors were recorded between 5:00 a.m. and 8:00 a.m. in Tra Linh commune (Da Nang) and Mang But commune (Quang Ngai), approximately 20 km apart. One day earlier, three earthquakes measuring 2.8 to 3.4 had also occurred in Mang But.

Mr. Nguyen Xuan Anh, Director General of the Institute of Earth Sciences, noted that although the events were reported under Da Nang, most of the epicenters were actually located in the former Quang Nam province, not within Da Nang’s urban area.

“These earthquakes are associated with a seismic source zone in the former Quang Nam area, particularly near Kon Plong and the Song Tranh 2 hydropower reservoir,” he said, adding that the area has previously experienced reservoir-induced seismicity, including a magnitude 4.7 earthquake on November 15, 2012.

The Institute assessed that seismic activity in the area is generally weak to moderate, with low risk.

Since 2021, more than 1,000 earthquakes have been recorded in the Kon Plong area (formerly Kon Tum province). Experts identify this as a low-intensity seismic zone, with maximum expected magnitudes not exceeding 5.5. Most of these tremors are believed to be induced earthquakes, linked to water accumulation in hydropower reservoirs, which increases pressure on fault lines.

Some earthquakes may still be felt over a wider area. On March 21, a magnitude 3.6 earthquake in Mang But was clearly felt by coastal residents for several seconds.