时间尺度的冲击过程在chondritic和火星石
P Beck1, Ph Gillet, A El Goresy
1Laboratoire de Sciences de la Terre, CNRS UMR 5570, Ecole Normale Supérieure de Lyon et Université Lyon I, 46 allée d'Italie, 69364 Lyon Cedex 7, France. pbeck@ens-lyon.fr
Nature
|June 24, 2005
概括
研究石冲击波揭示了撞击体大小和火山口的动态. 石撞击比火星上的撞击更大,更长,为行星积聚提供了洞察力.
科学领域:
- 行星科学 行星科学
- 太空化学 太空化学
- 撞击坑研究 撞击坑研究
背景情况:
- 陆地行星的积聚和石的传递被广泛模拟.
- 冲击石为太阳系进化和撞击过程提供了洞察力.
研究的目的:
- 确定一个石和火星石的峰值冲击压力和冲击持续时间.
- 在母体上推断撞击器尺寸和石坑尺寸,使用冲击缩放定律.
主要方法:
- 在石的剪切融化静脉中分析微量元素分布.
- 使用高压矿物质数据推断冲击事件持续时间.
- 应用冲击缩放规律来估计冲击器和石坑的大小.
主要成果:
- 冲击持续时间和冲击器大小在石中显著更大 (约. 1秒,5公里) 与火星石相比 (大约. 10 ms, 100 m) 的时间.
- 火星石撞击器和火山口的大小与火星火山口的数值建模一致.
结论:
- 火星石为了解火星撞击过程提供了宝贵的数据.
- 表明最近的火星石可能起源于火星的局部区域.
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