クレタチウムと三次期の境界の粘土の衝撃石英:地球規模の分布の証拠

B F Bohor, P J Modreski, E E Foord

Science (New York, N.Y.)

|May 8, 1987

まとめ

世界的に発見されたショッククォーツは,クレタセアス-第3期境界で大規模な小惑星の衝突が確認されています. この衝突は,地球を包む塵の雲を生み出し,アルバレス衝突仮説を裏付けました.

科学分野:

地質学地質学地質学
惑星科学は惑星科学である.
パレオントロジー・パレオントロジー

背景:

クレータ紀-三次紀 (K-T) の境界線は,重大な大量絶滅の出来事を示しています.
アルバレス衝突仮説は,地球外生命体の衝突が,この絶滅を引き起こしたことを示唆している.

研究の目的:

K-T境界でショックを受けたクォーツの証拠を調査するために.
衝撃エジェクトの地球規模分布を確認するためです.

主な方法:

K-T境界粘土層からのクォーツ粒子の分離.
結晶学を用いたクォーツの平面的な特徴の分析.
X線 difrakcionは,ショック誘発のストライクを識別するために.
屈折率の測定. 屈折率の測定. 屈折率の測定. 屈折率の測定. 屈折率の測定. 屈折率の測定. 屈折率の測定. 屈折率の測定.

主要な成果:

プラナー形状のショッククォーツは,世界の複数の場所 (ヨーロッパ,太平洋,ニュージーランド) で発見されています.
合理的な結晶学的平面にインデックスされた平面的な特徴.
X線 difraktionによって,衝撃による線が形成されたことが確認されました.
衝撃を受けたクォーツ粒子の折射率の低下が観察されました.

結論:

世界中で衝撃クォーツの存在は,K-T境界で大規模な衝突イベントが確認されています.
衝突エジェクタは,塵の雲で地球全体に広がった.
アルバレス衝突仮説を支持する強力な証拠を提供します.

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