2025年1月7日西藏定日M_(S)6.8级强震地表同震形变特征与房屋建筑震损分析  

Coseismic deformation and seismic damage assessment of buildings from the M_(S)6.8 earthquake in Dingri,Xizang,on January 7,2025

作　　者：谭莎莎 杨莹辉 许强[1] 王运生[1] 赵伟华[1] 罗永红[1] 陈强[2] 吉锋[1] TAN Shasha;YANG Yinghui;XU Qiang;WANG Yunsheng;ZHAO Weihua;LUO Yonghong;CHEN Qiang;JI Feng(State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China;Southwest Jiaotong University,Department of Remote Sensing and Information Engineering,Chengdu 610031,China)

机构地区：[1]地质灾害防治与地质环境保护全国重点实验室(成都理工大学),成都610059 [2]西南交通大学遥感与信息工程系,成都610031

出　　处：《成都理工大学学报(自然科学版)》2025年第2期212-222,共11页Journal of Chengdu University of Technology: Science & Technology Edition

基　　金：国家社会科学基金重大项目(24&ZD164)。

摘　　要：2025年1月7日,西藏自治区日喀则市定日县发生了M_(S)6.8级强震,此次强震造成了重大人员伤亡及大量房屋倒塌。综合利用国内外雷达卫星影像,成功提取了定日地震地表形变场,结果显示此次地震的发震断裂为近南北走向的登么错断裂,同震断层破裂长度约45 km,并以正断层运动为主,且地表形变集中在断层西侧上盘区域,最大形变量达2.1 m。结合InSAR相干系数、地震前后雷达影像后向散射系数以及现场调查,开展了震区房屋建筑震损分析。结果表明倒塌房屋集中在断裂以西上盘,该特征与地表形变强烈区吻合;且震区房屋倒塌比例随距断裂距离增加呈衰减趋势。其中登么错西北的长所乡及周边村落为房屋倒塌最为严重区域,部分村落房屋倒塌比例超过75%,而震中所在查吉村及临近区房屋倒塌现象相对较弱,与野外调查震中未见断层地表破裂的震损现象一致。研究成果为地震灾害评估和震后重建工作提供了重要科学依据。On January 7,2025,an M_(S)6.8 earthquake struck Dingri County,Shigatse City,Xizang Autonomous Region,causing widespread building damage and casualties.This study integrates satellite radar imagery from multiple domestic and international sources to derive the surface deformation field of the Dingri earthquake.The results indicate that the earthquake was triggered by coseismic normal faulting along the seismogenic Dengmo Cuo fault,with a rupture length exceeding 45 km.The main surface deformation was concentrated on the western flank of the fault,with a maximum displacement of 2.1 m.InSAR coherence,pre-and post-earthquake radar backscatter coefficients,and field surveys were comprehensively utilized to assess building damage in the affected region.The analysis reveals that the house collapse rate decreases with increasing distance from the fault.The northwest lake shore region of Dengmo Cuo,including Changshuo township and nearby villages,suffered the most severe damage,with the house collapse rate exceeding 75%in some areas.In contrast,regions near the epicenter,such as Chaji village,experienced relatively minor damage,suggesting smaller coseismic fault displacement in the source region.Field investigations further confirmed the absence of significant surface rupture near the epicenter.

关 键 词：定日M_(S)6.8级强震 InSAR同震形变 同震断层破裂 房屋建筑震损分析 地震野外调查 

分 类 号：P237[天文地球—摄影测量与遥感]