オルビトリーナ (Orbitolina) は,クレタシオスのより大きなフォアミニファーで,フレンチキャップから:古海洋学的な意味合い
まとめ
より大きなホルミニフェラル属のオルビトリナ属,特にオルビトリナコノイドは,北大西洋で発見されました. この発見は,白亜期におけるフレンチ・キャップ地域における北極の影響を除いて,熱帯環境を示唆している.
科学分野:
- パレオントロジー・パレオントロジー
- マイクロパレオンタロジーとは
- ストラティグラフィー ストラティグラフィー
背景:
- より大きなフォラミニフェラル属のオルビトリーナ (Orbitolina) は,主に北緯33度以南の北米の発生地から知られている.
- オルビトリーナ属は,古代環境条件の重要な指標である.
研究 の 目的:
- 北大西洋の最も東端の西の大陸棚にOrbitolinaの発見を報告するために.
- この発見の古環境条件と古生物地理学的意味を決定する.
主な方法:
- 化石の識別とより大きなフォラミニフェラの分類.
- 宿主岩の堆積物学的分析 (粒子を支える石灰岩).
主要な成果:
- Orbitolina conoideaとして特定されたOrbitolina属は,北大西洋西部の大陸棚の46度30'Nで発見されました.
- オービトリナの豊富さは,熱帯性ネリティック環境を示しています.
- オルビトリナの存在は,早期または中期の白亜紀の間,フレンチ・キャップ地域における北極海の影響を排除する.
結論:
- この発見により,北米のオービトリーナ (Orbitolina) の知られている北の範囲が拡大した.
- フレムッシュ・キャップ地域は,白亜紀初期または中期に熱帯の条件を経験しました.
- クレタ紀のテシアンフォラミニフェラの古生物学地理学的モデルを再評価する必要がある.
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