1. Professor, School of Earth Sciences and Engineering, Nanjing Univ., 163 Xianlin Rd., Nanjing 210093, China (corresponding author).
2. Research Scholar, School of Earth Sciences and Engineering, Nanjing Univ., 163 Xianlin Rd., Nanjing 210093, China.
3. Professor, Ecole des Ponts ParisTech, Laboratoire Navier-CERMES, 6 et 8, avenue Blaise Pascal, Cité Descartes, Champs-sur-Marne, 77455 Marne-la-Vallée Cedex 2, France.
4. Professor, School of Earth Sciences and Engineering, Nanjing Univ., 163 Xianlin Rd., Nanjing 210093, China.