サルファート埋葬の制約は,ファネロゾーイク期の硫黄循環に当てはまります
Itay Halevy1, Shanan E Peters, Woodward W Fischer
1Environmental Sciences and Energy Research, Weizmann Institute of Science, Rehovot 76100, Israel. itay.halevy@weizmann.ac.il
Science (New York, N.Y.)
|July 24, 2012
まとめ
硫黄循環の研究は,硫酸エバポライトの埋葬率が変動し,海洋と大気化学に影響を及ぼすことを明らかにしています. ピライトの埋葬と気象はより安定しており,硫黄が地球の酸素レベルを調節する上で重要な役割を果たしていることを示唆しています.
科学分野:
- 地質化学 地質化学
- 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
- バイオジオケミカルサイクル
背景:
- 硫黄の循環は,堆積物有機物の呼吸,大気と海洋の酸化状態,海水の組成に不可欠です.
- 海水と沈殿貯水池の間の主要な硫黄の流れを制御する重要な要因は完全に理解されていません.
- これらの流れを理解することは,地球の長期的な地化学的調節を理解するために不可欠です.
研究 の 目的:
- サルファート蒸発性の埋葬フロースをファネロゾイク時代を通して定量化するために.
- 蒸発性の気象化と現代の河川硫酸塩流動との関係を調査するために.
- 硫酸塩とピライトの埋葬率の変動性と硫黄循環への影響を比較する.
主な方法:
- マクロストラティグラフィックデータを活用して,歴史的な蒸発石埋葬を再構築した.
- 耐候性蒸発物からの現代の河川硫酸流の寄与を分析した.
- 硫酸塩とピライトの埋葬と耐候率の比較.
主要な成果:
- 硫酸エヴァポライトの埋葬率は不安定で,エヴァポライトの形成と保存のための海洋環境の利用可能性と相関しています.
- 最近堆積した蒸発物の気象化は,現代の河川の硫酸塩流量の約半分を占めています.
- ピライト埋葬と気象変動の割合は,硫酸流と比較して,より高く,より一貫して,大きく均衡しています.
結論:
- 硫酸蒸発物の埋葬は,硫黄循環の重要な,しかし変数のある構成要素です.
- ピライト流の安定性は,地質的な時間尺度で大気中の酸素レベルを調節する硫黄循環のより支配的な役割を果たすことを示唆しています.
- 長期の硫黄循環とその地球システムへの影響を完全に理解するために,蒸発ダイナミクスに関するさらなる研究が必要です.
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