Lei Gao¹, Haijiang Zhang¹, Lina Gao², Hailiang Xin¹, Weisen Shen³ and Chuansong He⁴, (1)University of Science and Technology of China, School of Earth and Space Sciences, Hefei, China, (2)Southern University of Science and Technology, Department of Earth and Space Sciences, Shenzhen, China, (3)Stony Brook University, Syosset, United States, (4)Institute of Geophysics, China Earthquake Adminstration, Beijing, China