UCLA’s Leon and Joanne V.C. Knopoff Professor of Physics and Geophysics Linseng Meng and doctoral students Han Bao and Liuwei Xu found that powerful supershear earthquakes may be much more common than previously thought. The study analyzed all 6.7-or-greater magnitude strike-slip earthquakes worldwide since 2000, and identified 12 of the supershear type, or about 14%. Supershear quakes are caused when faults beneath the surface rupture faster than shear waves — the seismic waves that shake the ground back and forth — can move through rock. The effect creates pent up energy that is then released violently, resulting in an effect comparable to a sonic boom.

“Supershear earthquakes are potentially more destructive than other kinds of earthquakes because they are more effective at generating seismic waves, with more shaking, which could cause more damage,” Meng said. 

The findings suggest that disaster planning efforts should take into consideration whether nearby faults are capable of producing supershear earthquakes and, if so, take measures to prepare for a higher level of shaking and potential damage than could be caused by non-supershear earthquakes.

Learn more about how these destructive quakes can affect disaster planning at UCLA Newsroom.

Study Authors:

Han Bao, UCLA Earth, Planetary, and Space Sciences

Linsen Memg, UCLA Earth, Planetary, and Space Sciences

Image Source: Carol M. Highsmith/Library of Congress

Liuwei Xu, UCLA Earth, Planetary, and Space Sciences