1. Ocean University of China, Key Laboratory of Submarine Geosciences and Prospecting Techniques MOE, College of Marine Geosciences, Qingdao, China; Qingdao National Laboratory for Marine Science and Technology, Evaluation and Detection Technology Laboratory of Marine Mineral Resources, Qingdao, China; and Ocean University of China, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Qingdao, China. (corresponding author)