Rupture Process and Aftershock Distribution of the MS6.8 Earthquake in Dingri,Xizang,on January 7,2025
Dai Zonghui
Gao Jinrui
Wang Peng
An Yanru
Xu Liang
Li Dongmei
Li Cuiqin
Xu Changpeng
Tudeng Ciren
Abstract:To investigate the rupture mechanism of the MS6.8 earthquake in Dingri,Xizang,it inverted the rupture process of the mainshock using teleseismic waveforms and refined the hypocenter locations of the aftershock sequence through the double-difference relocation method.The results indicate that the rupture process lasted approximately 22 seconds,with unilateral propagation northward along the causative fault.The rupture extended for about 60 km,and the maximum slip reached 2.4 m,located roughly 30 km north of the mainshock,forming a co-seismic surface rupture zone that is consistent with the results of field geological surveys.The aftershock sequence exhibits a characteristic north-south distribution,which can be roughly categorized into three clusters.The earthquake distribution in the southern and central clusters indicates a complex fault structure and suggests the co-seismic activation of multiple secondary faults.Early aftershocks are concentrated in the low-slip regions at the periphery of the main rupture zone,complementing the high-slip areas(>1.5 m),consistent with the"stress shadow"effect.Subsequent aftershocks migrated southward and formed conjugate clusters trending NE-SW and NW-SE,revealing a multi-directional stress adjustment process in the post-seismic stage.These findings suggest that the regional tectonic stress field plays a significant role in controlling the rupture process,and that the aftershock distribution is closely related to post-rupture stress redistribution and regional tectonics.
Keywords:the MS6.8 earthquake in DingriXizangrupture processprecise locationseismogenic structureearthquakesstructural geology
Publication Date:2025-05-30
Online Publishing Date:2025-08-15(First online date of this platform, not the publication date of the document)
Pages:13( 1696-1708 )