The Da River fault zone causes earthquakes in Ninh Binh

The earthquake in Nho Quan district, Ninh Binh on the morning of May 27 was due to the activity of the Da River fault zone, a level 2 fault, according to experts from the Institute of Geophysics.

According to the Earthquake Information and Tsunami Warning Center (Institute of Geophysics), at 9:27 a.m. in Nho Quan district, a 3.4-magnitude earthquake occurred, with a depth of 17 km, accompanied by a small explosion and ground shaking. light. People in Thach Thanh and Ha Trung districts, Thanh Hoa province, and the area adjacent to the Nho Quan epicenter also felt a slight tremor.

Sharing with reporters, Associate Professor, Dr. Nguyen Hong Phuong, a seismologist at the Institute of Geophysics, commented that the tectonic earthquake occurred on the Da River fault zone, a tectonic fault quite famous for its level of activity. dynamic. The area where the incident occurred was in Ninh Binh, near big cities like Hanoi, so people clearly felt the tremors and explosions. "This is a weak earthquake, not a dangerous earthquake ," he said.

Location of epicenter. (Photo: Institute of Geophysics).

The Da River fault is the source of medium-level earthquakes in northern Vietnam. Associate Professor Hong Phuong said that fault zones are divided into two types (level 1 and level 2). Level 1 faults cause earthquakes like in Dien Bien, Tuan Giao, and Son La with strong earthquakes, while level 2 faults on Da River only cause small earthquakes.

Level 2 fault , separating two tectonic zones between the Son La and Da River zones according to the division outlined by geologists on the map. The fault zone is in the northwest of northern Vietnam, extending 450 km in the Northwest - Southeast direction, running from the Pa Nam Cum region (Lai Chau) through Quynh Nhai and to the East Sea at the mouth of Lach Giang.

In 2005, a similar battle was recorded in Ninh Binh. According to experts, the small earthquake has a natural disaster risk level of 0, but developments need to be regularly monitored because earthquakes often occur in chains. The Institute of Geophysics is monitoring further aftershocks and will notify if there is a high level of danger.

Dr. Nguyen Xuan Anh, Director of the Institute of Geophysics, also said that Ninh Binh is located on the Da River fault, an area where earthquakes have occurred, so the earthquake that occurred this morning is not unusual.

Tectonic earthquakes are caused by natural fault zones (a geological phenomenon related to tectonic processes in the Earth's crust. Usually faults often occur in places with unstable geological conditions). The earthquake in Ninh Binh occurred on the Da River fault zone, different from the type of stimulated earthquake that occurred in Kon Plong district, Kon Tum province. Earthquakes are stimulated by human impacts on the environment, specifically in hydroelectric areas where the reservoir layer is pressed down, causing stimulated earthquakes.