WEI WenXin,
JIANG ZaiSen,
SHAO DeSheng et al
.2018.Coseismic displacements from GPS and inversion analysis for the 2014 Ludian 6.5 earthquake.Chinese Journal Of Geophysics,61(4): 1258-1265,doi: 10.6038/cjg2018L0141
Abstract:Based on campaign and continuous GPS observations, this work analyzes the coseismic displacement and the slip distribution on the rupture of the 2014 Ludian 6.5 earthquake using the Steepest Decent Method (SDM) inversion method. The results show the left-lateral strain releases in the north-west direction, and the tensile strain releases in the north-east direction which is attenuated with the distance away from the fault. The displacement of the left-lateral shear strain controlled by the Baogunao-Xiaohe fault is weak in the vicinity of the Lianfeng and Zhaotong-Ludian faults, which indicates that the ruptured fault may not completely cut throuh the Zhaotong-Ludian fault and the ruptured fault is not a major feature in this area. The Zhaotong-Ludian fault has a certain right-lateral strain release, on which thrust strain release is not obvious, implying that the Zhaotong-Ludian fault is highly locked due to the south-east compression. The results of SDM inversion show that the Ludian earthquake is dominated by left-lateral and tensile motion, and the magnitude of the earthquake is around MW6.3. Combined with other research results, we suggest that the Lianfeng and Zhaotong-Ludian fault zones still have high seismic risk.
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