1. School of Geosciences, China University of Petroleum, Qingdao 266580, China
2. Laboratory for Marine Mineral Resources, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China
3. Longitude and Latitude Centre of Qingdao Eco-Tech Development Zone, Qingdao 266555, China
4. Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya 572000, China
5. Key Laboratory of Marine Geology and Environment, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China