TY - JOUR
T1 - Geochemistry of REY-rich mud in the Japanese Exclusive Economic Zone around Minamitorishima Island
AU - Fujinaga, Koichiro
AU - Yasukawa, Kazutaka
AU - Nakamura, Kentaro
AU - Machida, Shiki
AU - Takaya, Yutaro
AU - Ohta, Junichiro
AU - Araki, Shuhei
AU - Liu, Hanjie
AU - Usami, Ryo
AU - Maki, Ryota
AU - Haraguchi, Satoru
AU - Nishio, Yoshiro
AU - Usui, Yoichi
AU - Nozaki, Tatsuo
AU - Yamazaki, Toshitsugu
AU - Ichiyama, Yuji
AU - Ijiri, Akira
AU - Inagaki, Fumio
AU - Machiyama, Hideaki
AU - Iijima, Koichi
AU - Suzuki, Katsuhiko
AU - Kato, Yasuhiro
N1 - Funding Information:
This research was supported by JSPS through Grant-in-Aid Scientific Research (S) No. 22226015 and No. 15H05771 to Y.K. and Grant-in-Aid Scientific Research (B) No. 25289334 to K.N. We thank Y. Itabashi and C. Kabashima for their assistance with sample preparations and chemical analyses. We also appreciate K. Toyoda and an anonymous reviewer for constructive reviews. We are obliged to J. Ishibashi for his careful editing of the manuscript.
Publisher Copyright:
© 2016 by The Geochemical Society of Japan.
PY - 2016
Y1 - 2016
N2 - We report detailed lithological and chemical characteristics of deep-sea sediments, including rare-earth elements and yttrium-rich mud (REY-rich mud), in the Japanese Exclusive Economic Zone (EEZ) around Minamitorishima Island. Three research cruises obtained fourteen sediment cores collected by piston coring. Based on the visual descriptions and geochemical analysis of the sediment cores, we confirm the presence of REY-rich mud containing more than 400 ppm total REY (ΣREY) in the southern and northwestern areas of the Minamitorishima EEZ. The REY-rich mud layers are characterized by abundant grains of phillipsite, biogenic calcium phosphate, and manganese oxides, and are widely distributed in relatively shallow depths beneath the seafloor. In contrast, relatively thick, non-REY-rich mud lies near the seafloor in the northern areas of the EEZ. In the three cores from the southern part of the EEZ, we also confirm the presence of highly/extremely REY-rich mud layers. Further accumulation of geochemical data from the sediments will be required to constrain the extent of the highly/extremely REY-rich mud layers.
AB - We report detailed lithological and chemical characteristics of deep-sea sediments, including rare-earth elements and yttrium-rich mud (REY-rich mud), in the Japanese Exclusive Economic Zone (EEZ) around Minamitorishima Island. Three research cruises obtained fourteen sediment cores collected by piston coring. Based on the visual descriptions and geochemical analysis of the sediment cores, we confirm the presence of REY-rich mud containing more than 400 ppm total REY (ΣREY) in the southern and northwestern areas of the Minamitorishima EEZ. The REY-rich mud layers are characterized by abundant grains of phillipsite, biogenic calcium phosphate, and manganese oxides, and are widely distributed in relatively shallow depths beneath the seafloor. In contrast, relatively thick, non-REY-rich mud lies near the seafloor in the northern areas of the EEZ. In the three cores from the southern part of the EEZ, we also confirm the presence of highly/extremely REY-rich mud layers. Further accumulation of geochemical data from the sediments will be required to constrain the extent of the highly/extremely REY-rich mud layers.
KW - Deep-sea mineral resources
KW - Geochemistry
KW - Minamitorishima island
KW - REY-rich mud
KW - Rare-earth elements
UR - http://www.scopus.com/inward/record.url?scp=85007347084&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85007347084&partnerID=8YFLogxK
U2 - 10.2343/geochemj.2.0432
DO - 10.2343/geochemj.2.0432
M3 - Article
AN - SCOPUS:85007347084
SN - 0016-7002
VL - 50
SP - 575
EP - 590
JO - GEOCHEMICAL JOURNAL
JF - GEOCHEMICAL JOURNAL
IS - 6
ER -