2016年新疆阿克陶M_S6.7地震和呼图壁M_S6.2地震的余震触发研究

Study on Aftershock Triggering of the 2016 Aktao M_S6.7 and Hutubi M_S6.2 Earthquakes in Xinjiang

基于断层位错产生的静态位移计算理论,首先计算了2016年11月25日新疆阿克陶M_S6.7地震及2016年12月8日新疆呼图壁M_S6.2地震产生的库仑破裂应力变化,在此基础上,与余震活动的空间分布进行对比,分析了这2次主震对余震的应力触发作用。结果表明:阿克陶M_S6.7地震的余震活动主要发生于主震产生的库仑破裂应力的应力减小区域内,而呼图壁M_S6.2地震95%以上的余震都发生在震中附近的应力增加区域内。呼图壁M_S6.2地震产生的库仑破裂应力对地震活动有显著的应力触发作用,而阿克陶M_S6.7地震的对余震的应力触发作用不明显。

Based on the theory of static displacement calculation caused by the coseismic fault movement,the Coulomb failure stress induced by the Aktao MS6. 7 earthquake in Xinjiang occurred on November 25,2016 and the Hutubi MS6. 2 earthquake occurred on October 8,2016 were calculated. Furthermore,by comparing the spatial distribution of the aftershock activity,the stress triggering effects of two main shocks on aftershocks were analyzed.The results show that most of the aftershocks of the Aktao MS6. 7 earthquake occurred in the area where the Coulomb failure stress reduced by the main shock,and more than 95% of the Hutubi MS6. 2 aftershocks were lied in the area of increased stress near to the epicenter area. The Coulomb failure stress caused by the Hutubi MS6. 2 earthquake has a significant stress triggering effect on the seismicity,however,the stress triggering effect of the Aktao MS6. 7 earthquake is not obvious.