1. 1State Key Laboratory of Geodesy and Earth’s Dynamics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, Hubei, China
2. 2Geophysical Exploration Center, China Earthquake Administration, Zhengzhou, Henan, China
3. 3School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia, U.S.A.
4. 4Department of Surveying Engineering, Guangdong University of Technology, Guangzhou, Guangdong, China