1. Laboratory of Seismology and Physics of Earth’s Interior, School of Earth and Space Sciences, University of Science and Technology of China, 96 Jinzhai Road, Hefei 230026, China, zhang11@ustc.edu.cn
2. Also at Geophysical Exploration Center, China Earthquake Administration, 75 Wenhua Road, Zhengzhou 450002, China.
3. Geophysical Exploration Center, China Earthquake Administration, 75 Wenhua Road, Zhengzhou 450002, China
4. China Deep Exploration Center of the Chinese Academy of Geological Sciences, Key Laboratory of Earth Probe and Geodynamics, 26 Baiwanzhuang Avenue, Beijing 100037, China