青藏高原北部历史强震对2022年门源MS6.9地震及后续地震库仑应力触发作用  

Triggering effect of historical earthquakes in the northern Tibetan Plateau on the Coulomb stress of the 2022 Menyuan MS6.9 earthquake and subsequent earthquakes

作　　者：汤大委 葛伟鹏[1] 袁道阳 郑文俊 胡才博 TANG DaWei;GE WeiPeng;YUAN DaoYang;ZHENG WenJun;HU CaiBo(Gansu Lanzhou National Geophysical Observation and Research Station,Lanzhou Institute of Seismology,China Earthquake Administration,Lanzhou 730000,China;School of Earth Sciences,Lanzhou University,Lanzhou 730000,China;School of Earth Science and Engineering,Sun Yat-sen University,Guangzhou 510275,China;School of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国地震局兰州地震研究所,甘肃兰州地球物理国家野外科学观测研究站,兰州730000 [2]兰州大学地质科学与矿产资源学院,兰州730003 [3]中山大学地球科学与工程学院,广州510275 [4]中国科学院大学地球与行星科学学院,北京100049

出　　处：《地球物理学报》2023年第7期2772-2795,共24页Chinese Journal of Geophysics

基　　金：国家重点研发计划项目(2017YFC1500100);中国地震局科技星火计划项目(XH18048);甘肃省自然科学基金(17JR5RA340),中国地震局地震预测研究所基本科研业务专项(2014IESLZ05);国家自然科学基金(41304035,42172227)共同资助。

摘　　要：本文采用Burgers黏弹性模型计算1125年以来青藏高原北部历史强震对2022年1月8日青海门源M_(S)6.9地震单独和累积的库仑应力变化,分析历史强震对此次门源地震黏弹性触发作用及其对后续地震的影响.结果表明:(1)1920年海原M8½级地震、1927年古浪M8.0级地震和1954年山丹M7¼级地震对2022年门源地震的加载最为显著,分别相当于使门源地震提前7.6年、5.3年和5.2年;(2)1986年门源M_(S)6.4地震对2022年门源地震的卸载作用最明显,使其发生延迟14.4年左右,2016年门源M_(S)6.4地震使2022年门源地震延迟0.4年左右;(3)2021年玛多M_(W)7.3地震对2022年门源地震有较为显著的触发作用,门源M_(S)6.9地震对2022年1月23日哈拉湖M5.8级地震有触发作用,哈拉湖M5.8级地震对2022年3月17日肃南M5.1级地震及2022年3月26日哈拉湖M6.0级地震有较强的触发作用,而哈拉湖M6.0级地震又触发了2022年4月15日哈拉湖M5.4级地震.综合分析历史强震库仑应力演化结果和断层受历史地震库仑应力作用的影响,认为该区域应力积累处于较高水平,祁连山内部断层受到应力扰动时容易失稳滑动,其中门源地震区附近、祁连山西段哈拉湖北部、老虎山断裂西段、祁连山北缘断裂中段、昌马—俄博断裂中段、阿尔金断裂阿克塞段、托莱山断裂西段、鄂拉山断裂和大柴旦—宗务隆山断裂东段等断层段都处于库仑应力高值区域,应给予关注.We employ the Burgers viscoelastic model to investigate the Coulomb stress change on the Menyuan M_(S)6.9 earthquake that occurred on January 8,2022.We aim to explore the viscoelastic triggering effect of strong historical earthquakes in the northern Tibetan Plateau since 1125 AD on the Menyuan earthquake and its impact on subsequent earthquakes.The results reveal that the Haiyuan M8½earthquake in 1920,the Gulang M8.0 earthquake in 1927,and the Shandan M7¼earthquake in 1954 have the most significant loading effect on the Menyuan earthquake in 2022.These historical earthquakes advance the occurrence of the Menyuan earthquake by 7.6 years,5.3 years,and 5.22 years,respectively.Additionally,the 1986 Menyuan M_(S)6.4 earthquake has the most prominent unloading effect on the 2022 Menyuan earthquake,delaying its occurrence by approximately 14.4 years.Furthermore,the 2021 Madoi M_(W)7.3 earthquake has a significant triggering effect on the Menyuan earthquake in 2022,while the Menyuan M_(S)6.9 earthquake triggers the Hala Lake M5.8 earthquake on January 23,2022.The Hala Lake M5.8 earthquake has a strong triggering effect on the Sunan M5.1 earthquake on March 17,2022,as well as the Hala Lake M6.0 earthquake on March 26,2022.Finally,the Hala Lake M6.0 earthquake triggers the Hala Lake M5.4 earthquake on April 15,2022.Based on the comprehensive analysis of the Coulomb stress evolution results of strong historical earthquakes and the influence of faults by viscoelastic Coulomb stress of historical earthquakes,we conclude that the stress accumulation in this area is high.The internal faults of Qilian Mountain are prone to instability and sliding when disturbed by stress,including the vicinity of the Menyuan earthquake area,the northern part of Halahu Lake in the western part of Qilian Mountain,the western part of Laohushan fault,the middle part of the northern margin of Qilian Mountain,the middle part of Changma-Ebo fault,the Altyn Tagh Fault(Aksai segment),the western part of Tolaishan fault,Elashan fault,and Dachaidan-Zong

关 键 词：青藏高原北部 历史强震 门源M_(S)6.9地震 Burgers黏弹性模型 库仑应力变化 

分 类 号：P542[天文地球—构造地质学] P315[天文地球—地质学]