モンタナ州ヘール・クリーク地域における末期白期の絶滅: 壊滅的な絶滅に適合する
まとめ
モンタナ州のストラティグラフィック・エラーにより,白亜紀・三次紀の境界における移行期のファウナに関する誤った考えが生まれました. パレオセンのチャネルにおけるこれらのファウナの再評価は,地上の記録と海洋の記録を並べて,壊滅的な絶滅のイベントをサポートします.
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:
- モンタナ州ヘル・クリーク地域における不正確な層学相関は,最後の白亜紀における移行期脊椎動物群 (バグ・クリーク・アンチルス) の存在を前提としている.
- この仮説は,クレタセアス時代と地表期の境界で大災害が起こったという概念に異議を唱える.
研究 の 目的:
- ヘル・クリーク地域における移行期のファウナの層図的位置を再評価する.
- これらのファウナがクレタセアス・テリシアル境界における大惨事的な絶滅の出来事を支持するか否かを判断する.
主な方法:
- モンタナ州ヘル・クリーク地域における詳細な戦略分析.
- バグ・クリーク・アンチルス (Bug Creek Anthills) の生物の堆積環境の再調査.
主要な成果:
- 移行期のファウナは,白亜紀と地質の境界を切り抜けるパレオセンの運河に確立した.
- この再評価は,陸生動物と海生動物記録の不一致を解決するものです.
結論:
- 陸上の動物記録は,海洋記録と互換性があります.
- この発見は,クレタセウス・テリエリアの境界で大絶滅が起きたことを支持し,クレタセウスの最後の時期の移行期のファウナの存在を否定している.
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