Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5781606 | Tectonophysics | 2017 | 13 Pages |
Abstract
The rupture processes of the 2015 April 25 Gorkha earthquake and its strongest aftershock occurred on May 12 in Nepal are investigated by joint inversion of seismological and geodetic data. Synthetic test shows that the sedimentary layers in the source region play an important role in the rupture process inversion. Our optimized model of the mainshock shows that the rupture has a unilateral propagation pattern. The dominant mechanism is pure thrust with maximum slip of 5.8Â m, the rupture scale extends ~Â 60Â km along dip and ~Â 150Â km along strike, and the largest static stress change is ~Â 7.6Â MPa. The total seismic moment is 7.87Â ÃÂ 1020Â NÂ m, equivalent to Mw 7.9. Most seismic moment was released within 80Â s and the majority seismic moment was released at the first 40Â s. The rupture propagated in main slip asperity with a velocity of ~Â 3.0Â km/s. The strong aftershock magnitude is about Mw 7.3, and the peak slip is about 5.0Â m, close to the peak slip of the mainshock. Moreover, the slips of the mainshock and the aftershocks are in good complementary, suggesting a triggering relationship between them. Considering the strain accumulation, the Gorkha earthquake ruptured only part of the seismic gap alone, thus still poses high earthquake risk, especially in the west side of the mainshock rupture zone.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Earth-Surface Processes
Authors
Chengli Liu, Yong Zheng, Rongjiang Wang, Bin Shan, Zujun Xie, Xiong Xiong, Can Ge,