タイトルヨミ | シンジコ タイセキソウチュウ ノ シジミ カイガラソウ ノ ハッケン ト ソノ イギ
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日本語以外のタイトル | A Discovery of a Corbicula Bed in the Holocene Sediments of Lake Shinji and Its Significance
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ファイル | |
言語 |
日本語
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著者 |
徳岡 隆夫
中村 唯史
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内容記述(抄録等) | An interesting occurrence of large fossilised corbiculas(Corbicula japonica, which lives in brackish water), coexisting with living specmens, has been known by fishermen at a transitional area between shelf and slope in the northern central part of Lake Shinji at a depth of about 3 m. The possibility of the occurence being an ancient shell mound is low, as no man-made remains have been dredged in the present area. The fossilified corbicula give a ^14C age of 1926+124-122 yrs B.P. This age suggests that the corbiculas flourished to form the corbicula bed at the late Holocene regression stage, as Lake Shinji is known changed from a marine embayment in the Jomon Age to a brackish coastal lagoon in the Yayoi Age. Echo-sounding surveys in the northern central part of Lake Shinji show that a reflector exists less than 1.5 metre below the bottom and this is traceable to the subaqueous exposure of the corbicula bed. The reflector could be penetrated by a newly-devised gravity corer, and it was found that the reflector definitely consists of corbiculas. It is inferred that Corbicula japonica flourished in great numbers in accordance with a drastic environmental change in Lake Shinji, from the embayment of Jomon Age to the brackish lake of Yayoi age.
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主題 | Lake Shinji
coastal lagoon
Corbicula japonica
^14C age
echo-sounding survey
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掲載誌名 |
Laguna : 汽水域研究
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巻 | 4
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開始ページ | 77
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終了ページ | 83
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ISSN | 21852995
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発行日 | 1997-03
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NCID | AN10439529
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出版者 | 島根大学汽水域研究センター
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資料タイプ |
紀要論文
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ファイル形式 |
PDF
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著者版/出版社版 |
出版社版
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部局 |
研究・学術情報本部 エスチュアリー研究センター
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他の一覧 |