1. State Key Laboratory for Mineral Deposits Research and School of Earth Sciences and Engineering, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
2. State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Nanjing 210008, China
3. Department of Earth System Science, Fukuoka University, Fukuoka 814-0180, Japan