ベンシックフォラミニフェラと古気温における異性同位体分離は,再評価された
Science (New York, N.Y.)
|April 10, 1970
まとめ
異なるベンシックフォラミニフェラ種は,異なる酸素同位体値を示し,古気温の控除を妨げました. pelagic foraminifera と benthic foraminifera の両者は,温度変化ではなく,海洋酸素-18の変動を反映した.
科学分野:
- パレオセアノグラフィー
- マイクロパレオンタロジーとは
- イソトープ地球化学 イソトープ地球化学
背景:
- ベンシック・フォラミニフェラは,過去の海洋状態を再構築するために不可欠です.
- 酸素同位体分析は,一般的な古気候のプロキシである.
研究 の 目的:
- 酸素イソトープを用いた古気温再構築のためのベンシックフォラミニフェラの信頼性を調査する.
- フォラミニフェラの酸素同位体変動が温度や海洋の組成を反映しているかどうかを判断する.
主な方法:
- ベンシックフォラミニフェラの異なる種からの酸素同位体値の分析.
- 同じ堆積水の中核レベルから採取したベンティック型とペラジック型フォラミニフェラの同位体データを比較.
主要な成果:
- 同じ堆積層のベンシックフォラミニフェラ種は,異なる酸素同位体値を示した.
- pelagic と benthic foraminifera の種は,同様の同位体変化パターンを示しました.
- 観測された同位体変動は,海洋水の酸素-18の組成の変化に起因する.
結論:
- ベンシック・フォラミニフェラ (Benthic foraminifera) の酸素同位体値は種特異であり,古気温の再構築に直接使用することはできません.
- pelagicと benthic foraminiferaの両方の酸素同位体変動は,主に海洋水の同位体組成の変化を示しています.
- 混合フォラミニフェラ集合体の酸素イソトープにのみ依存することは,不正確な古気候解釈につながる可能性があります.
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