北京时间2023年2月23日8时37分,在塔吉克斯坦距我国边境线较近区域发生MW 6.8地震。利用新疆地区强震台站(国家烈度速报与预警工程项目建设台站)数据,对此次地震进行破裂过程的快速反演。基于地震破裂方向性效应,通过台站峰值加速度与经验地震动衰减关系对比,确定地震的主破裂面。得到的破裂模型表明,此次地震为单侧破裂,破裂面呈NE—SW走向展布,整个破裂过程持续约25 s,释放地震矩为1.8×1019 N·m,破裂长度约32 km,最大滑动量约1.8 m,最大破裂点位于震中NE方位约28 km处。基于新疆地区强震数据记录的震源破裂过程的快速产出,为临近我国边境地区强震的震后破裂过程应急产出积累了经验。
At 8:37 Beijing Time on February 23, 2023, the MW 6.8 earthquake occurred in Tajikistan near the border with China. Based on the data of Xinjiang strong earthquake station (National Intensity Quick Report and Early Warning Project construction station), the rupture process of the earthquake was quickly retrieved. The main rupture plane of the earthquake is determined by comparing the peak acceleration of the station with the attenuation of the empirical ground motion and the seismic rupture directivity effect. The rupture model shows that the earthquake was unilateral rupture, the rupture surface was distributed in NE-SW trend, the whole rupture process lasted about 25 s, the seismic moment was 1.8×1019 N·m, the rupture length was about 32 km, the maximum slip momentum was about 1.8 m, and the maximum rupture point was located about 28 km NE direction of the epicenter. The rapid output of focal rupture process based on strong earthquake data recorded in Xinjiang region has accumulated experience for emergency production of post-earthquake rupture process of strong earthquakes near China’s border areas.
2024,45(3): 1-8 收稿日期:2023-12-12
DOI:10.3969/j.issn.1003-3246.2024.03.001
基金项目:中国地震科学实验场项目协作任务(项目编号:DQJB23Z03-04)
作者简介:戴丹青(1990—),男,工程师,主要从事地震预警运维和震源破裂过程研究工作。E-mail:daidanqing@seis.ac.cn
*通讯作者:席楠(1986—),男,高级工程师,主要从事地震烈度速报与地震预警研究。E-mail:xinan314@seis.ac.cn
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