著者 Osae, Shiloh| 加瀬 克雄| 山本 雅弘|
発行日 1995-09-20
出版物タイトル Okayama University Earth Science Report
2巻
1号
資料タイプ 紀要論文
著者 Frank k, Nyame| 加瀬 克雄| 山本 雅弘|
発行日 1995-09-20
出版物タイトル Okayama University Earth Science Report
2巻
1号
資料タイプ 紀要論文
著者 山本 雅弘| 加瀬 克雄| Harada, Kaori|
発行日 1998-09-20
出版物タイトル Okayama University Earth Science Report
5巻
1号
資料タイプ 紀要論文
著者 井上 佳紀| 加瀬 克雄|
発行日 1999-09-20
出版物タイトル Okayama University Earth Science Report
6巻
1号
資料タイプ 紀要論文
JaLCDOI 10.18926/ESR/13871
フルテキストURL earth_science_reports_010_1_1.pdf
著者 冨谷 尚士| 井上 佳紀| 加瀬 克雄|
抄録 In order to know the reason why the Cu/Zn-Pb ratios of skarn-type deposits related with the ilmenite-series granitic rocks are markedly higher than those related with the magnetite-series, comparative mineralogical studies were carried out for the two types of granitic rocks in the Chugoku district. An attention was focused on the be-havior of Zn during the crystallization of granitic magma, because Zn contents of mafic minerals can be obtained by non-destructive electron microprobe analyses. Microscopic observation indicats that no sphalerite occurs in the magnetite-series granitic rocks, which im-plies that the magmas corresponding to the granitic rocks were undersaturated in respect to ZnS. Electron micro-probe analyses revealed that the Fe/(Fe+Mg) ratios of mafic minerals such as biotite and hornblende in the ilmen-ite-series granitic rocks are remarkably higher than those in the magnetite-series, and the Zn contents are posi-tively correlated with the Fe/(Fe+Mg) ratios in the ilmenite-series granitic rocks. Also the Zn/Fe rations seem to be slightly higher in the ilmenite-series granitic rocks. In contrast, the correlation between Zn contents and Fe/(Fe+Mg) ratios is ambiguous in magnetite-series granitic rocks. With a progress of crystallization differentiation, therefore, Zn may be removed more effectively in the il-menite-series granitic magma, and the contents may be growing scarce in the fractionated ilmenite-series granitic magma. On the other hand, magnetite-series granitic magma probably increases the Zn-contents in the advanced stage of the crystallization. The hydrothermal fluids genetically related to the fractionated magnetite-series grani-tic magma are likely to be enriched in Zn, being favorable for the formation of Zn-rich deposits.
キーワード Magnetite-series Ilmentie-series Granitic rocks Zn contents Mafic minerals Ore deposit
出版物タイトル Okayama University Earth Science Report
発行日 2003-12-20
10巻
1号
出版者 岡山大学理学部地球科学教室
出版者(別表記) Department of Earth Sciences Faculty of Science, Okayama University
開始ページ 1
終了ページ 10
ISSN 1340-7414
NCID AN10506284
資料タイプ 紀要論文
言語 English
著作権者 岡山大学地球科学研究報告編集委員会
論文のバージョン publisher
NAID 120002310429
Sort Key 1
Eprints Journal Name esr
JaLCDOI 10.18926/ESR/13850
タイトル(別表記) 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
フルテキストURL ESR_12_1.pdf
著者 Gena, Kaul| 千葉 仁| 加瀬 克雄|
抄録 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℃.
キーワード Sn-bearing chalcopyrite Pt-bearing bismuthinite Active sulfide Chimmey Yonaguni Knoll IV Okinawa Trough seafloor hydrothermal system
出版物タイトル Okayama University Earth Science Report
発行日 2005-12-31
12巻
1号
出版者 岡山大学理学部地球科学教室
出版者(別表記) Department of Earth Sciences Faculty of Science, Okayama University
開始ページ 1
終了ページ 5
ISSN 1340-7414
NCID AN10506284
資料タイプ 紀要論文
言語 English
著作権者 岡山大学地球科学研究報告編集委員会
論文のバージョン publisher
NAID 120002310444
Sort Key 1
Eprints Journal Name esr