Online ISSN : 1880-5973
Print ISSN : 0016-7002
ISSN-L : 0016-7002
Special Issue: Front Edge of Submarine Mineral Resources Research in Japan (Part 2)
Discovery of extremely REY-rich mud in the western North Pacific Ocean
Koichi IijimaKazutaka YasukawaKoichiro FujinagaKentaro NakamuraShiki MachidaYutaro TakayaJunichiro OhtaSatoru HaraguchiYoshiro NishioYoichi UsuiTatsuo NozakiToshitsugu YamazakiYuji IchiyamaAkira IjiriFumio InagakiHideaki MachiyamaKatsuhiko SuzukiYasuhiro KatoKR13-02 Cruise Members
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Supplementary material

2016 Volume 50 Issue 6 Pages 557-573


We have discovered deep-sea mud that is extremely enriched in rare-earth elements and yttrium (together called REY) in the Japanese Exclusive Economic Zone around Minamitorishima Island, in the western North Pacific Ocean. The maximum total REY concentration reaches approximately 7000 ppm, which is much higher than that reported for conventional REY deposits on land and other known potential REY resources in the ocean. The extremely REY-rich mud is characterized by abundant phillipsite and biogenic calcium phosphate. In addition, the stratigraphic layer with the highest REY concentration occurs just ~3 m beneath the seafloor. The shallow burial of these strata together with the high REY content, especially those of heavy rare-earth elements, suggest that the newly discovered extremely REY-rich mud may be a promising REY resource.

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© 2016 by The Geochemical Society of Japan
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