2024年1月23日新疆乌什7.1级地震震源参数的初步分析

北京时间2024年1月23日2时9分,新疆阿克苏地区乌什县(41.26°N,78.63°E)发生7.1级地震。中国地震预警网于震后12.2 s产出首报预警信息,中国地震台网中心于震后3 min发布自动速报结果,震后13 min发布正式速报结果,同时联合多家单位启动地震应急产品产出工作,产出震源参数、地震构造、历史地震、余震精定位、震源机制和震源破裂过程等应急产品。结果显示,本次地震是一次发生在青藏高原西缘的逆冲型地震事件,余震展布呈NEE向; 主震破裂持续时间约15 s,主要能量约在震后8 s释放,最大位移量约2.3 m,破裂长度约32 km; 极震区推测烈度达Ⅷ度,区域涉及乌什县、阿合奇县,面积约4614 km²; 震中附近多个台站峰值加速度值大于该区设防标准,存在造成部分房屋和道路损坏的可能,经对比,与实际震害调查结果相吻合。

Preliminary analysis of source parameters of the Wushi M7.1 Earthquake on January 23,2024,Xinjing Uygur Autonomous Region

At 2:9 on January 23,2024,Beijing time,an earthquake of magnitude 7.1 occurred in Wushi,Aksu Prefecture,Xinjing Uygur Autonomous Region(41.26°N,78.63°E). The China Earthquake Early Warning Network issued the first early warning results in 12.2 seconds after the earthquake. The China Earthquake Networks Center released the automatic rapid report results in 3 minutes after the earthquake and the official rapid report results in 13 minutes after the earthquake. Cooperated with multiple units,the China Earthquake Networks Center produced emergency products,including source parameters,seismic tectonics,historical earthquakes,aftershock location,source mechanisms and source rupture process. The results showed that the earthquake was a thrusting event that occurred on the western margin of the Qinghai-Tibet Plateau,with the aftershock distributed in a NEE direction. The duration of the rupture was about 15 seconds,and the majority energy released in 8 seconds after the earthquake. The maximum slip reached 2.3 meters,and the rupture length was about 32 kilometers. The predicted intensity of the epicenter area reaches VIII,involving Wushi county and Aheqi county,with a total area of about 4614 km². The peak acceleration values of multiple stations near the epicenter were greater than the fortification standards of the area,which may cause damage to some houses and roads,which is consistent with the actual seismic damage investigation results.