凍結氷河期と炭素同位体分離の始まり
Nicholas L Swanson-Hysell1, Catherine V Rose, Claire C Calmet
1Department of Geosciences, Princeton University, Princeton, NJ 08544, USA.
まとめ
世界的な炭素循環のシフトは,地球の歴史と結びついています. 新しい炭素同位体データは,冷凍時代の炭酸と有機物質の分離を明らかにし,海洋条件の変化を示唆しています.
科学分野:
- 地質科学は地質科学である.
- 古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
- バイオジオケミストリー バイオジオケミストリー
背景:
- 世界的な炭素循環の混乱は,古地理学,氷河化,海洋の酸素化に関連しています.
- 注目すべきエディアカラン期の炭酸炭素同位体遠足は,以前,大きな海洋有機炭素貯蔵庫によって説明されていました.
研究 の 目的:
- 凍土期における炭素同位体の解離を調査する.
- オーガニック・カーボン・プール・成長のモデルと,海洋化学との関連をテストする.
主な方法:
- 炭酸塩と有機物の炭素同位体データの分析.
- 海洋化学と河川の流れ条件の再構築.
主要な成果:
- 約8億2000万年前から7億6000万年前まで,炭素同位体分離は観察されなかった.
- 炭素イソトープの完全な解離は,ストルチアとマリノア氷河期 (冷凍期) の間に起こった.
- 有機炭素プールの増加は,鉄が豊富で硫酸塩が少ない深海の条件と関連している可能性があります.
結論:
- この発見は,エディアカランの炭素同位体遠征に関する以前のモデルに異議を唱えている.
- 海洋化学,特にFe:S比は,冷凍時代の有機炭素プールを調節する上で重要な役割を果たしました.
- 氷河期の出来事は,海洋環境と地球規模の炭素循環に大きな影響を及ぼしました.
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