pelagic 堆積物における酸化フロント: 金属に富んだ層のダイアゲネティックな形成
Science (New York, N.Y.)
|May 23, 1986
まとめ
定期的に堆積する堆積物により,安定していないダイアゲネティック系が形成されます. この過程で鉄とマンガンが酸化され,海洋の堆積物の中で説明できない鉄に富んだ層が形成されます.
科学分野:
- 地質化学 地質化学
- 海洋学 海洋学 海洋学
- 堆積物学 堆積物学 堆積物学 堆積物学 堆積物学
背景:
- 海洋の堆積物は,堆積過程によって影響を受けます.
- ダイアゲネシスは,堆積後に堆積物の組成を変えます.
- 堆積物の中で鉄が豊富な層の形成は,まだ十分に理解されていない.
研究 の 目的:
- 周期的な渦巻岩の堆積から生じるダイアゲネティック系を調査する.
- 海洋堆積物における説明できない鉄濃厚層の形成メカニズムを説明する.
主な方法:
- マデラ・アビサール平原の堆積物核を分析した.
- ダイアゲネティックなプロセスをシミュレートするために数値モデルを使用した.
- 進んだ酸化フロントで鉄,マンガン,有機炭素の酸化を調査した.
主要な成果:
- 定期的な渦巻堆積は,非安定状態のダイアジェネティックシステムにつながります.
- 酸化フロントは下に向かって移動し,酸素や窒素酸塩のような酸化物質を消費します.
- このモデルは,特定の非安定状態の条件下で,鉄分豊富な層の形成を成功裏に予測しています.
結論:
- この研究は,非安定状態のダイアゲネシスによる鉄豊富な層の形成を説明しています.
- モデルの予測は,自然の海洋堆積物における観測された特徴と一致しています.
- この研究は,海洋堆積物学において以前説明できなかった現象を明らかにしている.
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