Comprehensive research on deep-sea metalliferous sediments as a new mineral resource

2014 Fiscal Year Final Research Report

• Project/Area Number: 22226015
• Research Category: Grant-in-Aid for Scientific Research (S)
• Allocation Type: Single-year Grants
• Research Field: Earth system and resources enginnering
• Research Institution: The University of Tokyo
• Principal Investigator: YASUHIRO Kato 東京大学, 工学(系)研究科(研究院), 教授 (40221882)
• Co-Investigator(Kenkyū-buntansha): IWAMORI Hikaru 独立行政法人海洋研究開発機構, 地球内部物質循環研究分野, 分野長 (80221795) ; NAKAMURA Kentaro 東京大学, 大学院工学系研究科, 准教授 (40512083)
• Co-Investigator(Renkei-kenkyūsha): FUJINAGA Koichiro 東京大学, 大学院工学系研究科, 特任研究員 (90409673) ; NOZAKI Tatsuo 独立行政法人海洋研究開発機構, 海底資源研究開発センター, 研究員 (10553068)
• Project Period (FY): 2010-04-01 – 2015-03-31
• Keywords: 海底鉱物資源 / 資源探査 / グローバル物質循環

Outline of Final Research Achievements

We discovered a deep-sea sediment with high concentration of rare-earth elements and yttrium (REY), termed as “REY-rich mud”, is widely distributed in the Pacific and Indian Oceans. The REY-rich mud constitutes a new resource for REY, essential for modern high-tech products. Our results of bulk sediment geochemistry, synchrotron X-ray radiation analysis, and statistical multivariate analysis demonstrated that the REY-rich mud occurs via accumulation processes of REY in hydrothermal Fe-Mn particulates and biogenic apatite with very low sedimentation rates. In the Japanese exclusive economic zone around Minamitorishima Island, we also discovered “extremely REY-rich mud” containing ~20 times higher REY contents compared to on-shore Chinese deposits. The future development of REY-rich mud has been included in the latest Japanese “Basic Plan on Ocean Policy”. We are now deploying various efforts to develop the mud through collaboration among government, industry, and academia.

Free Research Field

工学