New study sheds light on mysterious "supershear" quakes

0 Comments | AFP, June, 2008

PARIS (AFP) — A French-Turkish team of seismologists on Thursday said they had found evidence about the impacts of a rare but extremely violent earthquake called a supershear.

In a supershear, a pulse of energy can rip along the fault at up to 21,600 kilometres (about 13,000 miles) per hour -- many times faster than the speed of sound -- and can inflict immediate and potentially massive damage to buildings in the vicinity.

These quakes are not frequent and only occur on particular faults that are in a straight line, as this allows the pulse to be propagated without hitting an obstacle, rather as a car can speed along a straight road but slows at corners.

The devastating May 12 quake that hit China's southwestern province of Sichuan was not a supershear, but...