まとめ
環南極流はおよそ3000万年前に形成された. これは,南極大陸が南タスマン山脈から分離した後のオリゴセーン時代に起こった.
科学分野:
- パレオセアノグラフィーとは
- 地質学 地質学 地質学
- 南極研究 南極研究
背景:
- 南大洋の海洋学史は,世界の気候の動態を理解する上で極めて重要です.
- 海洋ゲートウェイの開きは,海流システムと熱の分布に大きな影響を与えます.
研究 の 目的:
- 環南極流の形成のタイミングを決定するために.
- 流れの形成に繋がった古地理的出来事を調査する.
主な方法:
- オーストラリアとニュージーランド南の深海掘削.
- パレオセアノグラフィの条件を再構築するために堆積物核の分析.
主要な成果:
- 証拠によると,環南極流は約3000万年前に形成された.
- このタイミングは,南極大陸と南タスマンの最終的な分離と相関しています.
- オーストラリアが南極から北に漂うのは,2000万年前から始まった.
結論:
- オリゴセーン時代は,南大洋の古海洋学における重要な時期を象徴した.
- 環南極流の形成は,大陸の漂流と構造的分離によって引き起こされた.
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