Why was the earthquake in Myanmar so strong and large?

(CLO) The 7.7-magnitude earthquake that occurred on the afternoon of March 28 in Myanmar affected many areas, including Thailand, as a result of complex plate tectonic activities in the region.

Myanmar lies on the boundary between the Indian and Eurasian plates, where the two plates interact strongly. The Indian plate is constantly moving northward at a speed of about 5 cm per year, colliding directly with the Eurasian plate.

This movement creates enormous pressure, deforming the Earth's crust and forming major faults in the area. When the pressure that has built up over tens or hundreds of years reaches a critical level, energy is suddenly released, causing earthquakes.

Map showing the extent of the earthquake in Myanmar. The red and orange areas are the hardest hit, concentrated along the main fault. The black asterisk on the map is the epicenter of the earthquake, near the city of Mandalay. Photo: USGS

The latest earthquake was centered near the Sagaing fault, one of the largest faults in Southeast Asia. The fault runs about 1,200 kilometers from north to south in Myanmar, passing through major cities such as Mandalay and Yangon.

This is a strike-slip fault, where two blocks of land move horizontally. The sudden movement along this fault is the direct cause of the recent earthquake.

Many geological studies have shown that the Sagaing fault has a slip rate of about 18 - 20 mm per year, indicating that this area is at high risk of strong earthquakes. History has recorded many terrible earthquakes in Myanmar related to this fault, typically the 7.3 magnitude earthquake in Bago in 1930 that killed at least 550 people.

The earthquake on March 28 was about 10 km deep, and was classified as a shallow earthquake. Earthquakes at this depth often have widespread effects because the energy is not absorbed as much as it passes through the Earth's crust, resulting in strong shaking on the surface. This is why not only Myanmar but also many areas further away, including Thailand, Vietnam and China, felt the strong shaking.

Experts warn that the main quake could be followed by strong aftershocks in the coming days and weeks. These could trigger landslides, further damage to weak structures and impact on people's lives.

Ngoc Anh (according to USGS, AJ, Nautil)

Source: https://www.congluan.vn/tai-sao-tran-dong-dat-o-myanmar-lai-manh-va-rong-lon-den-vay-post340576.html