Xijun Liu, College of Earth Sciences, Guilin University of Technology, Guilin 541004, China, Guilin, China, Ji-Feng Xu, School of Earth Science and Resources, China University of Geosciences, Beijing, China, Wenjiao Xiao, IGG Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China and Paterno Castillo, UCSD-SIO, La Jolla, CA, United States