深海の炭酸塩における氷河期とホロセンの移行:選択的な溶解と安定した同位体信号
Science (New York, N.Y.)
|August 5, 1977
まとめ
ホロセンの溶解パルスは,西赤道太平洋のプランクトンであるフォラミニフェラ (Foraminifera) の同位体信号に大きく影響した. 約1万2000年前に始まったこの溶解は,氷河期からホロセンの移行期に酸素と炭素同位体に影響を与えた.
科学分野:
- パレオセアノグラフィー
- 海洋地質学 海洋地質学
- フォラミニフェライソトープ 地化学
背景:
- プランクトンフォラミニフェラの同位体記録は,過去の海洋状態に関する重要な洞察を提供します.
- 氷河期からホロセーン期への移行は,環境の変化が顕著な時期でした.
- 溶解効果を理解することは,古海洋学プロキシを正確に解釈する鍵です.
研究 の 目的:
- ホロセンの溶解パルスがプランクトンであるフォラミニフェラ (Foraminifera) の同位体信号に及ぼす影響を調査する.
- 西赤道太平洋における氷河期からホロセンの移行期における酸素と炭素同位体の変化を分析する.
- 溶解が同位体振幅に与える影響を定量化するために.
主な方法:
- 2つの箱のコアから近い距離のサンプルを分析.
- プランクトンであるForaminifera,特にGlobigerinifera sacculiferからの酸素と炭素同位体信号の検査.
- イソトープの変化を脱氷率と上層水の肥沃性との比較.
主要な成果:
- ホロセンの解消パルスは約12,000年前に始まり,その直後に強まりました.
- 溶解の始まりは,上層水の肥沃性の最大減少に先行した.
- 溶解は,ライソクリンの深さでGlobigerinifera sacculiferの同位体変化幅の20〜30%を占めました.
結論:
- ホロセンの溶解パルスは,西赤道太平洋の古海洋学的な再構築に影響を与える重要な要因である.
- Foraminiferaの同位体データを正確に解釈するには,溶解効果を考慮する必要があります.
- この研究は,脱氷期間の同位体変化を誘発する要因の複雑な相互作用を強調しています.
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