1. Assistant Professor, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China; Researcher, CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China; Researcher, China-Pakistan Joint Research Center on Earth Sciences, Islamabad 45320, Pakistan; formerly, Ph.D. Candidate, Dept. of Civil Engineering, Univ. of Tokyo, Tokyo 113-8656, Japan.