ペルミアのアンモノイドサイクロロボスはゼワン・フォーメーション,グルユル渓谷,カシミールから発見された
Science (New York, N.Y.)
|April 13, 1973
まとめ
アムノイド頭足類は,パレオゾーイク・メソゾーイク境界付近の岩層を相関させるための鍵です. カシミールで発見されたペルミア後期のアムノイド,サイクロロボス・ウォーカーリ (Cyclolobus walkeri) は,この重要な地質学的移行を理解するのに役立ちます.
科学分野:
- パレオントロジー・パレオントロジー
- ストラティグラフィー ストラティグラフィー
- 地質学 地質学 地質学
背景:
- アムノイド頭足類は,バイオストラティグラフィーの重要なインデックス化石である.
- ペルム・トライアスの境界は,大規模な大量絶滅のイベントを表しています.
- この境界を越えた層の正確な相関は,古代環境の変化を理解するために不可欠です.
研究 の 目的:
- ゼワン・フォーメーションでサイクロロボス・ウォーカリー (Cyclolobus walkeri) の発見を報告する.
- カシミールのペルミアン-トライアスク境界のバイオストラティグラフィック相関を磨くために.
- 最上層のパレオゾーイク時代の海洋生態系に関する理解に貢献する.
主な方法:
- 化石の識別と分類学的記述.
- グリュール渓谷のセクションのストラティグラフィック分析.
- アムモノイド組成に基づくバイオストラティグラフィック年代測定.
主要な成果:
- 後期ペルミア紀のアンモノイドサイクロロボス・ウォーカリー (Cyclolobus walkeri) の診断が確認されました.
- 標本はペルミアン-トライアスク接触の20メートル以下,ゼワン・フォーメーションで発見された.
- この発見は,この重要なセクションに,ペルミア後期 (最上位パレオゾーイク) のアンモノイド集合体が存在することを確認しています.
結論:
- サイクロロボス・ウォーカーリ (Cyclolobus walkeri) の発見は,古生代・中生代境界付近の層を相関させる上でその有用性を強化している.
- この化石は,カシミール地域における最上位ペルム紀の正確なマーカーを提供します.
- この発見は,この重要な時間帯におけるアンモノイド分布とバイオストラティグラフィーの理解を深める.
関連する概念動画
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