邢台老震区库仑应力演化及地震危险性分析  

Coulomb Stress Evolution and Seismic Hazard Analysis on the Xingtai Old Earthquake Region

作　　者：陈婷[1] 章阳 王晓山[1] 孙丽娜[1] CHEN Ting;ZHANG Yang;WANG Xiaoshan;SUN Lina(Hebei Earthquake Agency,Shijiazhuang 050021,China)

机构地区：[1]河北省地震局,石家庄050021

出　　处：《华北地震科学》2021年第4期50-56,共7页North China Earthquake Sciences

基　　金：河北省地震局强震发震构造与机理研究创新团队(DZ20180319009);2019年震情跟踪定向工作任务(2019010122);河北省地震科技星火计划青年项目(DZ20190419028)。

摘　　要：基于Burgers粘弹性层状模型,综合考虑同震位错和震后粘滞松弛效应,利用PSGRN/PSCMP程序计算地震破裂面上产生的库仑破裂应力变化,分析邢台地震序列中每次6级以上地震前的所有6级以上地震对本次地震的综合库仑破裂应力变化,探讨强震间的应力触发关系。结果表明:除3月26日6.2级地震外,其余地震均发生在库仑应力增加的应力触发区,与之前的6级以上地震存在很好的应力触发关系;根据邢台地震序列的库仑应力演化与5级以上地震活动关系讨论邢台老震区的地震危险性,认为5级以上地震发生在应力触发区概率达到71.9%,邢台老震区中强地震活动与库仑应力变化有很好的相关性,可将库仑应力动态演化特征应用到本区地震的中长期预测中,为后续中强震发生地点提供参考。Uing the PSGRN/PSCMP program,we calculated the Coulomb stress change on earthquake rupture surface based on the Burgers viscoelastic layer model,analyzed the comprehensive Coulomb failure stress change of all MS≥6 earthquakes before each MS≥6 earthquake in the Xingtai earthquake sequence,and explored the stress triggering relationship between strong earthquakes.The results show that,except for the March 26th magnitude 6.2 earthquake,all the earthquakes occurred in the stress triggering zone with increased Coulomb stress,and there were a good stress triggering relationship with the previous earthquakes of magnitude 6 and above.According to the coulomb stress evolution of the Xingtai earthquake sequences and the relationship between the activity of earthquakes of magnitude 5 and above and the old Xingtai earthquake seismic risk it is found that,the probability of the magnitude 5 or above earthquakes occurred in stress triggering zone is 71.9%.It shows that the seismic activities had a good correlation with the coulomb stress change in Xingtai old earthquake area.The coulomb stress dynamic evolution characteristics can be applied to the medium and long term prediction of earthquakes in this region,which can provide reference for the location of subsequent moderate and strong earthquakes.

关 键 词：邢台地震 库仑应力演化 粘弹性模型 应力触发 地震危险性 

分 类 号：P315.7[天文地球—地震学]