Abstract:
We use the data of mobile across-fault deformation at main tectonic areas in China up to the end of 2014, aided by analysis on time-space evolution for anomalies of fault deformation and the index of feature intensity and the result of GPS velocity field, to search the variation background of tectonic activities in large area and short-term precursor anomalies, possibly being related to the activities of strong earthquakes such as Lushan, Minxian-Zhangxian, Ludian and Jinggu Ms 6.5~7.0 earthquakes during 2013~2014 at the eastern margin of Qinghai-Tibet plateau. The results show that, ① this group strong earthquakes during 2013~2014 possibly had relationship with the general accelerating of tectonic activities at the eastern margin of Qinghai-Tibet plateau. ② Lushan Ms 7.0 and Minxian-Zhangxin Ms 6.6 earthquakes were located inside this monitoring area, reflecting obvious short-term precursor anomalies; But Ludian Ms 6.5 and Jinggu Ms 6.6 earthquakes outside this monitoring area reflected weaker short-term precursor anomalies.