[B-PT05] Decoding the history of Earth: From Hadean to Modern

[BPT05-01] The progress of research on REY-rich mud within the Minamitorishima EEZ

*Yasuhiro Kato^1,2,3, Koichiro Fujinaga^3,1, Kentaro Nakamura^1,2, Kazutaka Yasukawa^1,3, Junichiro Ohta¹, Yutaro Takaya^4,1, Koichi Iijima², Shiki Machida^2,1, Tatsuo Nozaki^2,1, Jun-Ichi Kimura², Katsuhiko Suzuki², Hikaru Iwamori^2,5 (1.Department of Systems Innovation, Graduate School of Engineering, University of Tokyo, 2.Japan Agency for Marine-Earth Science and Technology, 3.Chiba Institute of Technology, 4.Department of Resources and Environmental Engineering School of Creative Science and Enginerring, Waseda University, 5.Tokyo Institute of Technology)

Keywords:deep-sea mineral resource, REY-rich mud, Minamitorishima Island

Three years have passed since the amazingly fruitful research cruise KR13-02 resulted in a discovery of deep-sea mud extremely enriched in rare-earth elements and yttrium (REY) within the Japanese exclusive economic zone (EEZ) surrounding Minaimitorishima Island. The mud with maximum total REY content of ~8,000 ppm strongly attracts our attention as an unconventional and highly promising deep-sea mineral resource. Subsequent six cruises, i.e., MR13-E02, KR14-02, MR14-E02, MR15-E01 Leg 2 and Leg 3, and MR15-02, have highlighted that the southern part of the Minamitorishima EEZ appears to be the unique area where the “extremely REY-rich mud” lies at very shallow depth (2 to 4 m) below the seafloor. In the presentation, we report a general overview of our latest findings from various approaches to REY-rich mud in the Minamitorishima EEZ including chemical, physical, statistical and engineering techniques.