大型撞击结构的峰环形成过程中的岩石流化
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
概括
石撞击导致岩石大幅减弱,流动,然后恢复力量形成撞击环. 这项研究揭示了声流化是火山口机制的一个关键过程.
科学领域:
- 星球科学
- 地质学
- 撞击坑
背景情况:
- 陆地撞击结构表现出由上升的地岩形成的突出地形环.
- 这些岩石在形成火山口时的快速变形和随后的强度恢复尚不清楚.
研究的目的:
- 调查导致撞击坑环形成的岩石变形机制.
- 阐明大型冲击期间目标岩石的灾难性削弱和强度恢复过程.
主要方法:
- 分析来自奇克苏鲁布撞击结构的核心样本.
- 检查峰环岩石中的脆性和粘性变形.
主要成果:
- 观察到灾难性的岩石减弱,然后在坑形成过程中强度增加.
- 证据表明声流化是主要的最初石坑形成过程.
- 随后的火山口形成涉及到越来越多的局部断层.
结论:
- 声流化解释了目标岩石的初始快速流动和大规模变形.
- 从流体化到局部断层的过渡解释了撞击结构中的地形环的形成和维持.
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