Jiawei Jiang, University of Hong Kong, Hong Kong, Hong Kong, Bowen Meng, The University of Hong Kong, Department of Earth Sciences, Hong Kong, Hong Kong, Aifeng Zhou, Lanzhou University, Key Laboratory of Western China’s Environmental Systems (Ministry of Education), College of Earth and Environmental Sciences, Lanzhou, China, Weiguo Liu, Chinese Academy of Sciences, State Key Laboratory of Loess and Quaternary Geology, Xi'an, China, Marina Kolpakova, Nosibirsk State University, Novosibirsk, Russia, Sergey Krivonogov, Novosibirsk State University, Novosibirsk, Russia and Zhonghui Liu, The University of Hong Kong, Pok Fu Lam Road, Hong Kong