最新のパレオセンの熱的最大期における大量の炭素の供給源と運命を説明する
1Department of Geological Sciences, Rutgers University, Piscataway, NJ 08854, USA. Department of Geological Sciences and Marine Science Institute, University of California, Santa Barbara, CA 93106, USA. School of Earth Sciences, James Cook University, Townsville, Queensland 4811, Australia.
Science (New York, N.Y.)
|November 24, 1999
まとめ
5550万年前,ブレイク・ノーズからメタンが大量に放出され,地球温暖化,炭素循環の大規模な破壊,大量絶滅を引き起こした. これは,ガス水素解離仮説を裏付けている.
科学分野:
- パレオセアノグラフィー
- 地質化学 地質化学
- パレオントロジー・パレオントロジー
背景:
- パレオセーヌ・エオセーヌ熱最大 (PETM) は,地球温暖化が顕著な時期でした.
- PETMの正確なトリガーとメカニズムは,依然として研究対象です.
- ガス水素からメタンの放出は,炭素の急速な放出のための提案されたメカニズムです.
研究 の 目的:
- 過去の気候現象におけるメタンの放出の役割を調査する.
- 古代メタン放出の特定の場所とメカニズムを特定するために.
- メタンの放出と主要な環境的および進化的変化を相関させるため.
主な方法:
- ブレイク・ノースから採取された石質学,動物学,地震学,同位体学データの分析.
- メタンの放出イベントの証拠を探すために堆積物核の検査.
- 地質学的発見と世界の気候と炭素サイクルデータとの相関.
主要な成果:
- 証拠は,約5550万年前にブレイク・ノースで発生した生物学的メタンの大量放出を,海洋温暖化と主要な炭素循環の混乱と結びつけている.
- このイベントは,盆地動物の大量絶滅と,哺乳類のオーダー放射の発生と一致した.
- 関連する堆積物と地震データは,中間的な水温上昇,炭素の投入,炭酸溶解,酸素の減少を示しています.
結論:
- この発見は,過去の気候変動の原動力として,ガス水素解離仮説を裏付けている.
- ブレイク・ナースは,古代メタン放出の重要な場所として特定されています.
- 大量のメタンの放出は,海洋化学,気候,生物多様性に大きな影響を与えます.
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