| Item type |
デフォルトアイテムタイプ_（フル）(1) |
| 公開日 |
2023-03-18 |
| タイトル |
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タイトル |
Redistribution of REE, Pb and U by supergene weathering studied from in-situ isotopic analyses of the Bangombe' natural reactor, Gabon |
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言語 |
en |
| 作成者 |
Kikuchi, M.
Hidaka, Hiroshi
Horie, K.
Gauthier-Lafaye, F.
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| アクセス権 |
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アクセス権 |
open access |
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アクセス権URI |
http://purl.org/coar/access_right/c_abf2 |
| 権利情報 |
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権利情報 |
Copyright(c) 2007 Pergamon-Elsevier Science Ltd |
| 主題 |
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主題Scheme |
NDC |
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主題 |
450 |
| 内容記述 |
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内容記述 |
The isotopic analyses of rare earth elements (REE), Pb and U in several kinds of minerals from the clay and black shale layers above the Bangombe natural reactor, Gabon, were performed using a sensitive high-resolution microprobe (SHRIMP) to investigate the migration and retardation processes of fission products released from the reactor. REE isotopic data of the secondary minerals found in clays and black shales show that most of fission products were effectively trapped in the clays and not distributed into the black shales over the clays, which reveals that the clays play an important role in preventing fission products from spreading. Zircon crystals in the clays heterogeneously contain high-U regions (up to 28.3 wt%) with normal U-235/U-238 ratios (=0.00725) and significant amounts of fissiogenic REE, which suggest the occurrence of significant chemical fractionation between REE and U during the dissolution of reactor uraninite and the recrystallization of secondary U minerals. The Pb data suggest that galena grains in the clays were also formed by the mixing of the two components during a recent alteration event, and that a significant amount of Pb was derived from 2.05-Ga-old original uraninite rather than reactor uraninite. The U-Pb systematics of zircon provide chronological information on the old igneous activity associated with the basement rock formation at 2.8 Ga and geochemical evidence of the incomplete mixing of independent Pb and U sources. This result is consistent with previous chronological results in this area. |
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言語 |
en |
| 出版者 |
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出版者 |
Pergamon-Elsevier Science Ltd |
| 言語 |
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言語 |
eng |
| 資源タイプ |
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資源タイプ識別子 |
http://purl.org/coar/resource_type/c_6501 |
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資源タイプ |
journal article |
| 出版タイプ |
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出版タイプ |
AO |
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出版タイプResource |
http://purl.org/coar/version/c_b1a7d7d4d402bcce |
| 関連情報 |
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識別子タイプ |
DOI |
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関連識別子 |
10.1016/j.gca.2007.07.016 |
| 関連情報 |
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関連タイプ |
isVersionOf |
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識別子タイプ |
DOI |
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関連識別子 |
http://dx.doi.org/10.1016/j.gca.2007.07.016 |
| 収録物識別子 |
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収録物識別子タイプ |
ISSN |
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収録物識別子 |
0016-7037 |
| 収録物識別子 |
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収録物識別子タイプ |
NCID |
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収録物識別子 |
AA00655038 |
| 開始ページ |
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開始ページ |
4716 |
| 書誌情報 |
Geochimica et Cosmochimica Acta
Geochimica et Cosmochimica Acta
巻 71,
号 19,
p. 4716-4726,
発行日 2007-10
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| 旧ID |
21460 |
GCA_71_4716.pdf (2.5 MB)
