摘要
利用2011年1—6月云南地区的连续波形资料,采用背景噪声和波形互相关方法分别反演该地区的速度结构以及2011年3月24日缅甸7.2级地震前后60d的速度变化图像。同时,根据云南地区中小地震计算缅甸地震前后应变能释放响应比空间分布,并利用缅甸地震的震源参数,计算了缅甸地震对云南地区主要断裂产生的库仑破裂应力影响。结果显示:(1)禄劝至华坪一带、永定至泸水区域和通海至建水地区震后波速增加,同时该地区地震活动增强,相应断裂上库仑破裂应力增加,说明缅甸地震对这些区域具有加速构造活动的正影响;(2)小江断裂带以东马龙至宣威地区和南汀河断裂带以南临沧至景洪地区震后波速降低,地震活动减弱,断裂上库仑破裂应力降低,说明缅甸地震对该区域具有减缓构造活动的负影响。
The velocity structure and the velocity variation in the sixty days before and after the Myanmar earthquake（Ms 7.2） on March 24, 2011 are inverted by the ambient noise and cross-correlation method, using the continuous seismic waveform records from January to June, 2011 in Yunnan region. Meanwhile, the spatial response ratio distribution of strain energy release is obtained using moderate and small earthquakes, and the coulomb stress impacts in different faults caused by the Myanmar earthquake are calculated using the source parameters of the Myanmar earthquake. The results show that in Luquan- Huaping, Yongding- Lushui, and Tonghai- Jianshui regions, the velocities increase, and the seismic activity and coulomb stress in corresponding fault zones of these regions are enhanced, reflecting the positive impact on tectonic activities; in Malong- Xuanwei and Lincang - Jinghong regions, the seismic activity and coulomb stress in fault zone of these regions are decreased, reflecting the negative impact on tectonic activities.
出处
《地学前缘》
EI
CAS
CSCD
北大核心
2013年第3期35-44,共10页
Earth Science Frontiers
基金
地震科技星火计划项目(XH1032)
国家重点基础研究发展计划"973"项目(2008CB425704)
关键词
背景噪声方法
地震活动
库仑破裂应力变化
缅甸7
2级地震
云南地区
ambient noise method
seismic activity
Coulomb failure stress changes
Myanmar earthquake（MS 7.2）
Yunnan region
