China’s next large earthquake will probably occur less than 40 miles to the north-east of the one that devastated Lushan in Sichuan Province last year, according to new research published in the journal Seismological Research Letters.
The latest data available on the magnitude 6.6 tremblor, which killed around 200 people and injured nearly 12,000 in April, suggest that it was actually triggered by the Wenchuan quake, which killed about 90,000 people in 2008. Their epicenters were around 55 miles apart.
The area being studied is part of the Longmenshan fault, which runs between Tibet and Sichuan. Researchers compared data on the Lushan and Wenchuan quakes with those on aftershocks and stress changes in four other large quakes, including the one in New Zealand.
They found that powerful aftershocks like Lushan could happen along well-developed fault zones if that is where the greatest overall aftershock activity and stress change are exhibited.
Strain energy has been accumulating along the Longmenshan fault for over 1,000 years. After it was released by the Wenchuan event, the southern section of the fault became the next danger zone. Since the Lushan episode, however, the scientists believe that the area to the northeast of Lushan is the place to monitor, and could produce a quake of up to magnitude 7.
They noted, however, that a risk assessment map from the Global Seismic Hazard Assessment Program does depict the whole Longmenshan fault zone as “relatively safe,” AFP reported.