Author Yamanaka, Toshiro| Mizota, Chitoshi| Fujiwara, Yoshihiro| Chiba, Hitoshi| Hashimoto, Jun| Gamo, Toshitaka| Okudaira, Takamoto|
Published Date 2003-8
Publication Title Journal of the Marine Biological Association of the UK
Volume volume83
Issue issue4
Content Type Journal Article
JaLCDOI 10.18926/21085
Title Alternative Automatic measurement of oxygen isotope ratio of water samples
FullText URL pitsr_056_027_034.pdf
Author Chiba, Hitoshi| Sakai, Hitoshi| Yasutake, Masatoshi|
Abstract The automatic sample preparation system for oxygen isotope analysis of natural water samples was constructed. The system is essentially a modification of that originally designed by W. Dansgaard in the University of Copenhagen. Sixty water samples of 5 ml each are automatically equilibrated with CO(2) of 30 ml NTP each within 4.5 hours. The equilibrated CO(2) gases are successively measured for their oxygen isotopic ratios by an automatic mas-sspectrometer, VG903. The time required for the measurement of the 60 CO(2) samples is about 15 hours; thus approximately 20 hours are required to complete the isotopic measurements of 60 water samples. The accuracy of the oxygen isotopic analyses is about 0.1%. The result of oxygen isotopic analyses by the automatic preparation system agrees with that of the conventional method within about +0.1%. The results indicate that the automatic preparation system is applicable for the oxygen isotope analysis of natural water samples.
Publication Title 岡山大学温泉研究所報告
Published Date 1985-03-30
Volume volume56
Start Page 27
End Page 34
ISSN 0369-7142
language 日本語
File Version publisher
NAID 120002310952
JaLCDOI 10.18926/ESR/13850
Title Alternative 沖縄トラフ第四与那国海丘海底熱水系チムニーの錫を含む黄銅鉱と白金を含む輝蒼鉛鉱
FullText URL ESR_12_1.pdf
Author Gena, Kaul| Chiba, Hiroshi| Kase, Katsuo|
Abstract The active sulfide chimney ore sampled from the flank of the active Tiger chimney in the Yonaguni Knoll IV hydrothermal system, South Okinawa Trough, consists of anhydrite, pyrite, shalerite, galena, chalcopyrite and bismuthinite. Electron microprobe analyses indicated that the chalcopyrite and bismuthinite contain up to 2.4 wt. % Sn and 1.7 wt. % Pt, respectively. The high Sn-bearing chalcopyrite and Pt-bearing bismuthinite are the first occurrence of such minerals on the submarine hydrothermal systems so far reported. The results confirm that the Sn enters the chalcopyrite as a solid solution towards stannite by the coupled substitution of Sn 4+ Fe 2+ for Fe 3+ Fe 3+ while Pt enters the bismuthinite structure as a solid solution during rapid growth. The homogenization temperature of the fluid inclusions in anhydrite (220-310℃) and metasured end-member temperature of the vent fluids (325℃) indicate that the minerals are precipitated as metastable phases at temperature around 300℃. The Sn-bearing chalcopyrite and Pt-bearing bismuthinite expess the original composition of the minerals deposited from a hydrothermal fluid with temperatures of about 300℃.
Keywords Sn-bearing chalcopyrite Pt-bearing bismuthinite Active sulfide Chimmey Yonaguni Knoll IV Okinawa Trough seafloor hydrothermal system
Publication Title Okayama University Earth Science Report
Published Date 2005-12-31
Volume volume12
Issue issue1
Start Page 1
End Page 5
ISSN 1340-7414
language 英語
Copyright Holders 岡山大学地球科学研究報告編集委員会
File Version publisher
NAID 120002310444