Fault slip model of 2013 Lushan Earthquake retrieved based on GPS coseismic displacements

Lushan Earthquake (~Mw 6.6) occurred in Sichuan Province of China on 20 April 2013, was the largest earthquake in Longmenshan fault belt since 2008 Wenchuan Earthquake. To better understand its rupture pattern, we focused on the influences of fault parameters on fault slips and performed fault slip inversion using Akaike’s Bayesian Information Criterion (ABIC) method. Based on GPS coseismic data, our inverted results showed that the fault slip was mainly confined at depths. The maximum slip amplitude is about 0.7 m, and the scalar seismic moment is about 9.47×1018 N·m. Slip pattern reveals that the earthquake occurred on the thrust fault with large dip-slip and small strike-slip, such a simple fault slip represents no second sub-event occurred. The Coulomb stress changes (ΔCFF) matched the most aftershocks with negative anomalies. The inverted results demonstrated that the source parameters have significant impacts on fault slip distribution, especially on the slip direction and maximum displacement.