浅源地震动态触发综述及四川威远地区案例分析  

Review and case analysis of dynamic triggering of shallow earthquake in the Weiyuan area,Sichuan Province

作　　者：江子豪 储日升 盛敏汉 Jiang Zihao;Chu Risheng;Sheng Minhan(State Key Laboratory of Geodesy and Earth's Dynamics,Institute of Geodesy and Geophysics,Innovation Academy for Precision Measurement Science and Technology,Chinese Academy of Sciences,Wuhan 430077,China;College of Earth and Planetary Sciences,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院精密测量科学与技术创新研究院大地测量与地球动力学国家重点实验室,武汉430077 [2]中国科学院大学地球与行星科学学院,北京100049

出　　处：《地球与行星物理论评（中英文）》2024年第4期399-415,共17页Reviews of Geophysics and Planetary Physics

基　　金：国家自然科学基金资助项目(42325401,U20A2095,42374077,42004043);湖北省科技创新人才专项(2022EJD015)。

摘　　要：地震动态触发是指远场地震波传播到某些处于临界应力状态的区域,从而触发地震事件的现象,浅源地震是触发地震中最主要的类型.研究浅源地震动态触发不仅可以增强对发震机理的理解,还可以衡量地下浅部断层应力状态,对防震减灾具有重要意义.本文综述了地震动态触发可能的机制、判定方法,着重介绍了在不同构造背景下几个浅源地震动态触发的研究案例.此外,利用四川威远地区2015年11月至2016年11月的密集台阵连续记录,探究了页岩气开采区浅源地震活动性是否受到远震触发作用的影响.发现该地区地震活动性在2015年12月7日塔吉克斯坦MW7.4地震后的12小时内显著增加,展现出动态触发特征.然而,经过仔细分析塔吉克斯坦地震后威远地区地震的时间和空间分布特征,发现这些增强的地震活动迁移过程具有流体扩散的特征,推测这些浅源地震是工业注水活动诱发的可能性更大.Dynamic triggering refers to the phenomenon of teleseismic waves propagating to some areas in a near-critical stress state,thus triggering earthquakes.Shallow earthquakes are the type of earthquakes that are most commonly triggered.Researching the dynamic triggering of shallow earthquakes can enhance understanding of the seismogenic mechanism and produce additional information about the state of shallow faults,which has great importance for earthquake prevention and disaster reduction.This article reviews possible mechanisms and detection methods of dynamic triggering,focusing on several case studies of triggered shallow earthquakes in different tectonic settings.Furthermore,by using continuous recordings from a dense seismic array in the Weiyuan area of Sichuan Province from November 2015 to November 2016,we investigated whether seismic activities in the shale gas extraction areas were influenced by the dynamic triggering of teleseismic waves.The results revealed that the seismicity in the area increased significantly within 12 hours of the MW7.4 Tajikistan earthquake on December 7,2015,and exhibited characteristics of dynamic triggering.However,after carefully analyzing the temporal and spatial distribution of the earthquakes in the Weiyuan area following the Tajikistan earthquake,we found that the migration of the enhanced seismic activities exhibited characteristics of fluid diffusion,suggesting that these shallow earthquakes were more likely induced by industrial injection.

关 键 词：动态触发 库仑失效 流体迁移 浅源地震 

分 类 号：P315[天文地球—地震学]