[B-PT05] [EJ] 地球史解読：冥王代から現代まで

[BPT05-20] 南鳥島南方海域における超高濃度レアアース泥層の側方分布

*藤永 公一郎^1,2、安川 和孝^2,1、野崎 達生^3,2,4、町田 嗣樹^3,2、飯島 耕一^3,2、舘野 ひとみ²、川崎 健寛²、高橋 亜夕³、天川 裕史³、鳥本 淳司³、深海 雄介³、鈴木 勝彦³、中村 謙太郎²、加藤 泰浩^2,1,3、MR15-02 乗船者一同 (1.千葉工業大学・次世代海洋資源研究センター、2.東京大学・工学系研究科、3.海洋研究開発機構、4.神戸大学・理学研究科)

キーワード：レアアース、レアアース泥、南鳥島、海底鉱物資源

Recently, we discovered deep-sea sediment containing ~7,000 ppm of total rare-earth elements and yttrium (REY), which was termed ‘extremely REY-rich mud’ (Iijima et al., 2016), within the Japanese exclusive economic zone (EEZ) around Minamitorishima island. To clarify the mineralogical/chemical characteristics and distribution of REY-rich mud in the Minamitorishima EEZ, we conducted eight research cruises over the four years. In the MR15-02 cruise by R/V Mirai from June 22 to July 17, 2015, we focused on investigating the lateral continuity of the extremely REY-rich mud layer in the southern part of the Minamitorishima EEZ. During the cruise, we collected 16 sediment cores by piston coring from the southwestern to southeastern areas of the Minamitorishima EEZ. Here we report visual core descriptions and bulk chemical compositions of the deep-sea sediment core samples, and discuss the extent of a highly promising area for future development of REY-rich mud in the Minamitorishima EEZ.