Can San Andreas fault break at once? Study says maybe

LOS ANGELES (AP) - A new study suggests certain earthquake fault segments long thought to be stable may rupture and cause a mega-quake. 

That's what happened during the 2011 magnitude-9 quake in Japan that triggered a tsunami and during the 1999 magnitude-7.6 Chi-Chi quake in Taiwan. 

In both cases, scientists assumed that "creeping" segments in a fault would serve as a buffer and prevent the entire fault from unzipping. 

But a new study published online Wednesday in the journal Nature suggests this may not always be the case. 

This may have important implications for California's San Andreas Fault, which has a creeping section that separates the locked segments in Northern and Southern California.

The Associated Press