Large slip rate detected at the seismogenic zone of the 2008 M_W7.9 Wenchuan earthquake

Repeating microearthquakes were identified along the edge of the rupture area of the 2008 M_W7.9 Wenchuan earthquake. Slip rates at depths derived from seismic moments and recurrence intervals are found to be systematically larger than those observed at surface. This large deep slip rate may explain the odds about the occurrence of this unanticipated event. Our observations here suggested that seismic hazard could be underestimated if surface measurements alone are employed.