大きな衝突構造のピークリング形成中の岩石流化
Ulrich Riller1, Michael H Poelchau2, Auriol S P Rae3
1Institut für Geologie, Universität Hamburg, Hamburg, Germany. ulrich.riller@uni-hamburg.de.
Nature
|October 26, 2018
まとめ
隕石が衝突すると 岩が激しく弱まり 流れてきて 再び強くなって 衝突輪を形成します この研究はクレーターメカニズムにおける 重要なプロセスとして 音響流体化を示しています
科学分野:
- 惑星科学
- 地質学
- 衝突クレーター
背景:
- 地表の衝撃構造は,地殻の岩石によって形成された顕著な地形リングを示しています.
- クレーター形成中のこれらの岩の急速な変形と,その後の強さの回復は,まだ十分に理解されていません.
研究 の 目的:
- 衝突クレーターリングの形成に起因する岩石の変形メカニズムを調査する.
- 大規模な衝突時に標的岩の壊滅的な弱体化と強度回復のプロセスを解明する.
主な方法:
- チクスルブ衝突構造から採取した核サンプルを分析した.
- ピークリング岩の内部の脆性および粘性変形の検査
主要な成果:
- 破滅的な岩石の弱まりが観察され,その後にクレーター形成の際に強さが増加した.
- アコースティック流体化が 主要な初期クレーター形成過程であると 示唆されています
- その後のクレーター形成は 局所的な断層を増加させました
結論:
- アコースティック・フリューディゼーションは,最初の急速な流れと標的岩の大規模な変形を説明します.
- 流体化から局所的断層への移行は,衝突構造における地形環の形成と維持を説明する.
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