1. State Key Laboratory of Loess, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710061, China
2. Shaanxi Key Laboratory of Accelerator Mass Spectrometry and Application, Xi’an Accelerator Mass Spectrometry Center, Xi’an 710061, China
3. Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China
4. Department of Earth, Ocean and Ecological Sciences, Geomagnetism Laboratory, University of Liverpool, Liverpool L69 3GP, UK
5. School of Human Settlements and Civil Engineering, Xi’an Jiaotong University, Xi’an 710049, China
6. University of Chinese Academy of Sciences, Beijing 100049, China
7. Xi’an Institute for Innovative Earth Environment Research, Xi’an 710061, China
8. Isotope Climatology and Environmental Research Centre, Institute for Nuclear Research, Debrecen H-4026, Hungary
9. University of Arizona, Tucson, AZ 85721