まとめ
モンタナ州のクレタセウス-三次元の境界にあるイリジウムに富んだ粘土岩層には,ショッククォーツが含まれています. これらの鉱物は,地球外の大規模な衝突イベントの説得力のある証拠を提供します.
科学分野:
- 地質学 地質学 地質学
- パレオントロジー・パレオントロジー
- 惑星科学は惑星科学である.
背景:
- クレータ紀と三次紀の境界線は,地球の歴史における重要な移行をマークしています.
- 非海洋岩層は,陸上の古生物学的な環境に関するユニークな洞察を提供します.
- 異常なイリジウムの濃度は,しばしば地球外の出来事と関連付けられています.
研究 の 目的:
- クレタセア-第3期間の境界にある粘土岩層の鉱物学的組成を調べるために.
- この層で見つかったショックを受けたクォーツ粒子の起源を決定するために.
- 地球外生命体との衝突の証拠を提供するために.
主な方法:
- モンタナ州東部で岩石サンプルを採取するための地質学的なフィールドワーク.
- クレタセウス-第3期間の境界を正確に特定するために,パリノロジック分析を行いました.
- 光学顕微鏡検査および結晶分析を含むクォーツ粒子の鉱物学的検査.
- 平面形変形の特徴,アステリスマ,および変化した折射率などの衝撃変形の特徴の識別.
主要な成果:
- モンタナ州東部のパリノロジカル・クレタセウス-三次期の境界にある薄い粘土岩層が特定されました.
- この層は異常に高いイリジウム濃度を示しています.
- 粘土石の中のクォーツの粒子は,平面的特徴,星形,および屈折率の低下を含む衝撃変異の特徴的な特徴を示しています.
結論:
- 衝撃を受けたクォーツ粒子は,大きな地球外生命体による高速衝突の決定的な証拠です.
- 衝撃を受けた鉱物は,衝突時に平流層に放出されたシリシウム状の標的物質を表しています.
- この衝突イベントは,白亜紀・地質境界の地質・生物学的条件に大きな影響を及ぼした.
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