Item type |
紀要論文(ELS) / Departmental Bulletin Paper(1) |
公開日 |
1994-09-01 |
タイトル |
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タイトル |
ISOTOPIC EQUILIBRATION AGE OF Sm-Nd WHOLE-ROCK SYSTEM IN THE NAPIER COMPLEX (TONAGH ISLAND), EAST ANTARCTICA |
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 |
departmental bulletin paper |
ID登録 |
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ID登録 |
10.15094/00002757 |
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ID登録タイプ |
JaLC |
ページ属性 |
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内容記述タイプ |
Other |
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内容記述 |
P(論文) |
論文名よみ |
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その他のタイトル |
ISOTOPIC EQUILIBRATION AGE OF Sm-Nd WHOLE-ROCK SYSTEM IN THE NAPIER COMPLEX (TONAGH ISLAND), EAST ANTARCTICA |
著者名よみ |
オワダ, マサアキ
オサナイ, ヤスヒト
カガミ, ヒロオ
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著者名(英) |
OWADA, Masaaki
OSANAI, Yasuhito
KAGAMI, Hiroo
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著者所属(英) |
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en |
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Department of Mineral Science and Geology, Yamaguchi University |
著者所属(英) |
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en |
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Department of Earth Science and Astronomy, Fukuoka University of Education |
著者所属(英) |
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en |
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Institute for Study of the Earth's Interior, Okayama University |
抄録(英) |
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内容記述タイプ |
Other |
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内容記述 |
Whole-rock measurements of ^<143>Nd/^<144>Nd and ^<147>Sm/^<144>Nd are reported for gneisses which had undergone granulite-facies metamorphism in Tonagh Island from the Napier Complex, East Antarctica. Felsic and ultramafic gneisses in adjacent outcrops yield a well-defined isochron age of 2458±61 Ma with an initial ratio of 0.50897±0.00004 (initial εNd=-9.5±0.7). These gneisses show a granuloblastic microfabric overprinted by a pervasive intercrystalline texture. The negative εNd value suggests that the isochron age indicates re-equilibration of the isotopic system on a whole-rock scale at 2458±61 Ma. On the other hand, mafic gneisses which crop out as thin layers alternated with pelitic and felsic gneisses yield an isochron with an age of 3708±533 Ma. The mafic gneisses display a uniform granuloblastic texture. The age of 3708 Ma is older than c. 3070 Ma, which has been regarded as the earliest tectonothermal age in the complex. εNd values at 3708 Ma for individual mafic gneiss range from +1.3 to +3.3. The values are within the range of Archaean komatiites and basalts, suggesting that the mafic gneisses were derived from the depleted mantle at c. 3700 Ma. |
雑誌書誌ID |
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収録物識別子タイプ |
NCID |
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収録物識別子 |
AA1072335X |
書誌情報 |
Proceedings of the NIPR Symposium on Antarctic Geosciences
巻 7,
p. 122-132,
発行日 1994-09
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出版者 |
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出版者 |
National Institute of Polar Research |