1. State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
2. Department of Earth and Environmental Sciences, Università di Milano-Bicocca, Milano 20126, Italy
3. Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48109-1005
4. Department of Geosciences, University of Arizona, Tucson, AZ 85721
5. North China Electric Power University, Beijing 100096, China