鲜水河断裂带地震矩亏损的空间分布及2022年泸定M 6.8级地震  

Spatial Distribution of Seismic Moment Deficit in Xianshuihe Fault Zone and the 2022 Luding M 6.8 Earthquake

作　　者：尹力 周本刚[1] 任治坤[1] 罗纲 Yin Li;Zhou Bengang;Ren Zhikun;Luo Gang(State Key Laboratory of Earthquake Dynamics,Institute of Geology,China Earthquake Administration,Beijing 100029,China;School of Geomatics,Wuhan University,Wuhan 430079,China)

机构地区：[1]中国地震局地质研究所,地震动力学国家重点实验室,北京100029 [2]武汉大学测绘学院,湖北武汉430079

出　　处：《地球科学》2024年第2期425-436,共12页Earth Science

基　　金：国家重点研发计划项目(No.2022YFC3003501);中国地震局地质研究所基本科研业务专项(No.IGCEA2315);国家自然科学基金青年项目(No.41904089)。

摘　　要：2022年9月5日泸定M 6.8级地震发生在鲜水河断裂带南端的磨西断裂.该地震的发震机制以及未来该断裂段是否仍会发生强震是值得关注的科学问题.拟从地震能量积累与释放的角度来解释该地震的发震原因以及鲜水河断裂带未来的发震潜力.通过对比地震矩积累与释放的时空分布,发现地震大都发生在地震矩亏损的段落,并有填补地震矩亏损的趋势.此外,鲜水河断裂带至今存在3个显著的地震矩亏损段,均具发生6.5级以上地震的潜力.1786年康定M 7.6级地震发生之后,经过两百多年时间的积累,足以发生M 6.5级以上地震,而泸定M 6.8级地震仅释放了磨西断裂上部分的地震矩亏损,未来该断裂段仍具有发生强震的可能.On September 5,2022,an M6.8 earthquake located at the Moxi fault at the southern end of the Xianshuihe fault zone.The seismogenic mechanism of this earthquake and whether large earthquakes will occur in this fault section in the near future are scientific issues worth attention.This paper attempts to explain the seismogenic mechanism of the earthquake and the potential seismogenic potential of the Xianshuihe fault zone in the future from the perspective of the accumulation and release of seismic energy.By comparing the temporal and spatial distribution of seismic moment accumulation and release,it is found that earthquakes mostly occur in the period of seismic moment deficit,and there is a tendency to fill the moment deficit.In addition,there are three significant moment deficit segments in Xianshuihe fault zone.All of these moment deficit fault segments have the potential to produce earthquakes of magnitude 6.5 or greater.After the 1786 Kangding M 7.6 earthquake,the accumulation of 200 years is enough to produce an earthquake of M 6.5 or above.The Luding M 6.8 earthquake only released a small part of the moment deficit on the Moxi fault,and there is still a possibility of a major earthquake on this fault section in the future.

关 键 词：地震矩亏损 鲜水河断裂带 泸定M 6.8级地震 地震危险性分析 

分 类 号：P315[天文地球—地震学]