エディアカラン海洋の分層リドックスモデル.
Chao Li1, Gordon D Love, Timothy W Lyons
1Department of Earth Sciences, University of California, Riverside, CA 92521, USA. chaoli@ucr.edu
まとめ
エディアカラン時代には,海洋化学には,独特のエオシニックとフェルルギンゾーンが特徴でした. この層化された海洋モデルは,初期の動物の化石の分布を説明しています.
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
- エディアカラン時代 エディアカラン時代
- 初期の動物の進化は,
背景:
- エディアカラン時代 (6億35億5400万年前) は,環境の変化が大きく,最初のマクロスコープの動物が現れた.
- エディアカランの海洋化学を理解することは,初期の生命の進化の軌道を説明する上で極めて重要です.
- 以前の研究では,エディアカラの深海の地化学的リドックス条件が矛盾していることを示唆していた.
研究 の 目的:
- エディアカラン時代の詳細な空間と時間の海洋化学を再構築する.
- 南中国の南華盆地におけるエディアカラン時代の環境条件を調査する.
- 矛盾する地化学データを調和させ,初期のメタゾアンの化石記録を説明するために.
主な方法:
- 中国南部の南華盆地にあるドゥシャントウ岩層の分析.
- エディアカランの海洋化学の詳細な空間と時間の再構築.
- 海洋層分化と再酸化条件をシミュレートするための地球化学モデリング.
主要な成果:
- コンチネンタルシェルフのエオシニック (無毒および硫化) 水の転移性ゾーンの証拠が見つかりました.
- シェルフ・オイシニアと共存する[Fe (II) ]濃厚な深海が発見された.
- ダイナミックに維持された層状の海洋で,エディアカラン全域で同時代の酸化,硫化,および鉄質地帯があり,低濃度の海洋硫酸塩が好ましい.
結論:
- この研究は,以前に対立する地球化学的酸化還元条件を調和させる層状のエディアカラン海洋のモデルを提示しています.
- この海洋化学モデルは,初期のメタゾーン化石の不規則な時間分布を理解するための枠組みを提供します.
- この発見は,エディアカラン期における海洋化学と初期の動物進化の複雑な相互作用を強調している.
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