| 摘要: |
| 计算了2000年以来南美板缘强震(先前地震)对2014年4月1日智利北部MS8.2主震、2014年4月3日MS7.6强余震以及本次主震对其后续余震的应力触发作用，研究结果表明：先前地震在主震震源机制解2个节面上产生的库仑应力变化均为正；采用不同的有效摩擦系数，在主震破裂面上产生的库仑应力变化超过阈值(0.01MPa)的子元最低占22.2%，库仑应力变化为正子元的比率最低和最高分别为74.3%、 95.5%。先前地震和主震在4月3日MS7.6地震震源机制解的2个节面上产生的库仑应力变化也均为正，且远大于触发阈值；最低有58.2%的破裂面子元上库仑应力变化超过触发阈值，最低有64.0%的破裂面子元上库仑应力变化为正。故先前地震有利于本次主震的发生，先前地震及本次主震又有利于MS7.6强余震的发生。根据全球CMT目录搜索到的8次余震震源机制解资料，计算了本次主震在后续余震震源机制解节面上的库仑破裂应力变化，计算结果显示，主震对其后续余震的触发效果不明显，由于余震资料的有限性，主震对余震的触发作用还有待于进一步研究。 |
| 关键词: 库仑破裂应力变化 应力触发 震源破裂模型 震源机制解 |
| DOI： |
| 分类号: |
| 基金项目:中国地震局教师基金项目(20140102)、中央高校基本科研业务专项资金(创新项目团队资助计划)(ZY20110101)共同资助 |
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| Primary research on the 2014 MS8.2 Chile earthquake triggering by large earthquake occurred on the boundary of south American plate since 2000 |
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Sheng Shuzhong1,2) Wan Yongge1,2) Huang Jichao3) Li Xiang1) Shi Yanbin1)
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1)Institute of Disaster Prevention，Sanhe 065201，Hebei, China；2)Institute of Geophysics，China Earthquake Administration，Beijing 100081，China；3)Lanzhou Institute of Seismology，China Earthquake Administration，Lanzhou 100045，China
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| Abstract: |
| We did a primary research on the stress triggering effect on the mainshock of April 1,2014 MS8.2 earthquake in northern Chile and its strong aftershock of April 3,2014 MS7.6 earthquake by large earthquakes occurrimg on the boundary of south American plate since 2000，and the stress triggering effect on the subsequent aftershocks by the mainshock. The results show that the previous earthquakes are beneficial to the occurrence of the mainshock，and the previous earthquake and the mainshock have triggering effects on the strong aftershock of MS7.6 earthquake. The Coulomb stress change on the two nodal plane of the mainshock's focal mechanism is positive，which was caused by the previous earthquake. Using different friction coefficients，the minimum ratio is 22.2% for the fault segment of the mainshock's rupture plane whose Coulomb stress change exceeds the threshold(0.01MPa). The minimum and maximum ratio of the positive Coulomb stress change fault segments are 74.3% and 95.5% respectively. The Coulomb stress change is positive on the two nodal plane of the April 3,2014 MS7.6 earthquake，which was caused by the previous earthquake and the mainshock，and is considerably larger than the stress triggering threshold. The minimum ratio of the fault segment with Coulomb stress change bigger than threshold is 58.2%，and the minimum ratio of the fault segment with positive Coulomb stress change is 64.0%. 8 aftershocks focal mechanism data was collected from Global CMT catalogue，the Coulomb stress change on each aftershock nodal plane was calculated. The study results show that the mainshock's triggering effect on the aftershock is not obvious，and needs further studing，because the limited data of aftershocks were used in this research. |
| Key words: Coulomb failure stress change Stress trigging Earthquake rupture model Focal mechanism |
