行星科学:由低速度撞击形成的流星坑
1Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona 85721, USA. jmelosh@lpl.arizona.edu
Nature
|March 11, 2005
概括
石坑的形成涉及一颗铁石以大约12公里/秒的速度撞击地球. 这种低于预期的撞击速度解释了火山口中没有显著的撞击融化岩石.
科学领域:
- 地质地质地质地质地质地
- 行星科学 行星科学
- 冲击石坑的形成
背景情况:
- 石坑,亚利桑那州,是第一个公认的陆地石撞击结构.
- 它已被广泛研究,但它的形成机制仍然部分无法解释.
研究的目的:
- 为了研究导致石坑形成的石撞击速度.
- 为了解决关于缺乏冲击融化岩石的差异.
主要方法:
- 从石坑的地质数据的分析.
- 撞击动态的建模.影响动态的建模.
主要成果:
- 铁石的表面撞击速度被确定为大约12公里/秒.
- 这个速度明显低于以前假定的值 (15-20公里/秒).
结论:
- 较低的撞击速度解释了在石坑观察到的撞击融化岩石的有限体积.
- 这一发现修订了我们对火山口的形成和相关冲击过程的理解.
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