初期のプロテロゾイク期の微生物化石と,ソコマン鉄形成の近現代的なクォーツセメント化,カナダ
Science (New York, N.Y.)
|January 30, 1981
まとめ
ソコマンとガンフリントの形成の初期のプロテロゾイク期の微生物化石は,形態学的に似ている. 初期の生命のコミュニティの違いは,生態学的であり,進化的ではありません,鉄の形成の内のペロイドに微生物化石が発見されています.
科学分野:
- パレオントロジー・パレオントロジー
- 地質学 地質学 地質学
- 天体生物学 アストロバイオロジー
背景:
- 初期のプロテロゾーイク時代の鉄層は,重要な微生物の化石を宿している.
- 古代地球環境における微生物の生命は,初期の進化と居住可能性についての洞察を提供します.
研究 の 目的:
- ソコマン鉄層の初期のプロテロゾイク期の微生物化石集合とガンフリント層の微生物集合を比較する.
- 初期の微生物コミュニティにおける観察された差異が,生態学的か時間的かを判断する.
- 微生物化石の保存と砂状鉄の形成におけるシリカの凝固との関係を調査する.
主な方法:
- ソコマン鉄層の微生物化石の形態学的分析.
- ソコマンの微生物化石集合と,ガンフリント・フォーメーションとベルチャー・スーパーグループからの公表データとの比較.
- 鉄の形成の石版分析により,マイクロ化石の分布とシリカの凝固を理解する.
主要な成果:
- ソコマン・アイアン・フォーメーションの微生物化石は,形態学とコミュニティ構造において,ガンフリント・フォーメーションの微生物化石と区別がつかない.
- ソコマン・アセンブラージは,ベルチャー超群のビッター・スプリングスのようなサイアノバクテリアと同時代である.
- 砂状鉄の形成の微生物化石はペロイドに限定され,シリカセメントには存在しない.
- 証拠は,近現代的なシリカセメント化と,これらの形成における一般的な初期のセメント化を示唆しています.
結論:
- 初期のプロテロゾイク期の主要な微生物群の違いは,主に生態学的であり,進化的ではない.
- マイクロ化石の保存は,堆積環境とダイアゲネシス,特にシリカセメント化に関連しています.
- 初期のプロテロゾイク期の微生物生態系は,同様の進化的制約の中で生態学的多様性を示した.
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