2025年1月7日西藏定日6.8级地震的快速产出参数  

Quick output parameters related to the 7 January 2025 M6.8 earthquake in Dingri County,Xizang

作　　者：陈鲲[1] 杨婷[1] 王永哲[1] 郭祥云[1] 张喆 张旭[1] 刘瑞丰[1] Chen Kun;Yang Ting;Wang Yongzhe;Guo Xiangyun;Zhang Zhe;Zhang Xu;Liu Ruifeng(Institute of Geophysics,China Earthquake Administration,Beijing 100081,China)

机构地区：[1]中国地震局地球物理研究所,北京100081

出　　处：《地震科学进展》2025年第3期164-171,共8页Progress in Earthquake Sciences

基　　金：国家重点研发计划(2022YFC3003505)资助。

摘　　要：2025年1月7日9时5分(北京时间)西藏定日发生6.8级地震。中国地震局地球物理研究所在震后启动快速地震应急响应,组织相关领域研究人员对此次地震的震源参数、震源机制、破裂过程和地震辐射能量等进行了估计,余震序列进行了重定位,基于震源破裂过程进行了地震动强度图模拟、InSAR同震形变场模拟。结果表明,此次地震发生在申扎—定结断裂系的登么错断裂西侧,以正断机制为主,主要持续时间约20 s,并呈现非对称双侧破裂特征,破裂主要朝北拓展,极有可能破裂到了地表;余震主要呈近南北向分布,震源深度集中在5~23 km;极震区震动烈度可能达Ⅸ度以上,可能的受灾范围超过30000 km^(2);此次地震引起了显著的地表同震位移,最大水平向位移达到0.29 m、垂直向位移达到-0.75 m。At 09:05 on January 7,2025(Beijing time),a magnitude 6.8 earthquake occurred in Dingri,Xizang Autonomous Region.The Institute of Geophysics,China Earthquake Administration launched a rapid earthquake emergency response after the earthquake,and organized researchers in relevant fields to estimate the source parameters,source mechanism,rupture process,and seismic radiation energy of the earthquake.The aftershock sequence was repositioned,and seismic intensity maps and InSAR coseismic deformation field simulations were conducted based on the source rupture process.The results indicate that the earthquake occurred on the west side of the Dengmocuo fault in the Shenzha-Dingjie fault system,with a main normal fault mechanism and a duration of about 20 seconds.It also exhibited asymmetric bilateral rupture characteristics,with the rupture mainly extending northward and most likely reaching the surface.Aftershocks are mainly distributed in a nearly north-south direction,with focal depths concentrated between 5~23 km.The seismic intensity in the extreme earthquake zone may reach seismic intensity IX or above,and the possible affected area may exceed 30000 km^(2).This earthquake caused significant surface coseismic displacement,with a maximum horizontal displacement of 0.29 m and a vertical displacement of−0.75 m.

关 键 词：震源参数 破裂过程 余震重定位 地震动强度图预测 地震辐射能量 同震形变场 

分 类 号：P315[天文地球—地震学]