In the left panel, regions identified by Chilieh et al (2011) as having a large slip deficit are shown as the ‘Most overdue’ patches. These are the sites where the megathrust is stuck and is accumulating stress at the highest rate, as inferred from GPS measurements. But today’s shock did not strike in or near one of these stuck patches, perhaps because the rupture area of a M=7.1 quake, about 50 x 50 km, is too small to be resolved by GPS.

In the left panel, regions identified by Chilieh et al (2011) as having a large slip deficit are shown as the ‘Most overdue’ patches. These are the sites where the megathrust is stuck and is accumulating stress at the highest rate, as inferred from GPS measurements. But today’s shock did not strike in or near one of these stuck patches, perhaps because the rupture area of a M=7.1 quake, about 50 x 50 km, is too small to be resolved by GPS.

In the left panel, regions identified by Chilieh et al (2011) as having a large slip deficit are shown as the ‘Most overdue’ patches. These are the sites where the megathrust is stuck and is accumulating stress at the highest rate, as inferred from GPS measurements. But today’s shock did not strike in or near one of these stuck patches, perhaps because the rupture area of a M=7.1 quake, about 50 x 50 km, is too small to be resolved by GPS.