Friday’s earthquake in Myanmar ruptured along the Sagaing Fault, a major fault that is part of the complicated tectonic plate structure of the Tibetan Plateau. The fault formed when the Indian subcontinent rammed into Asia tens of millions of years ago.
The Sagaing fault is the crack in the earth that separates two tectonic plates moving in opposite directions. Those plates are moving past each other at a rate of 0.7 inches (18 mm) per year — a significant amount of movement. If you build a fence across this fault line, it will shift in different directions and would be 7 inches apart in 10 years. That movement represents the stress that builds up along the fault and is released every decade or so in a massive earthquake.
Here’s more on the earthquake:
- Friday’s earthquake is certainly the largest to hit Myanmar since 1946 and likely the strongest in modern times. The 1946 quake was estimated to be 7.6 to 7.7 and also occurred along the Sagaing Fault.
- Friday’s earthquake is the first 7.0-magnitude or greater earthquake in Myanmar since 1991, when a 7.0 struck about 100 miles north of Friday’s.
- A 7.7-magnitude earthquake struck just across the border in China about 200 miles east of the current quake in 1988, according to the US Geological Survey. It killed 730 people.
The last time there was a quake on land of such magnitude was the 2023 Turkey earthquake, which killed more than 50,000 people.
The Myanmar earthquake has a similar shaking and loss estimate as the Turkey quake did at the time: The United States Geological Survey warned the Turkey quake exposed about 750,000 people to violent shaking; the Myanmar quake exposed around 800,000 people to violent shaking. Significantly, Myanmar has double the number of people exposed to violent and severe (level 8 and 9) shaking, nearly 5 million versus the Turkey earthquake’s 2.7 million.