1. Xi’an AMS Center, State Key Laboratory of Loess and Quaternary Geology, Shaanxi Key Laboratory of AMS Technology and Application, Institute of Earth Environment, CAS, Xi’an 710061, China
2. Xi’an Jiaotong University, Xi’an 710049, China
3. Beijing Normal University, Beijing 100875, China
4. Xi’an Institute for Innovative Earth Environment Research, Xi’an 710061, China