热带至中度的雪和冰在火星上的积累,流动和冰结
J W Head1, G Neukum, R Jaumann
1Department of Geological Sciences, Brown University, Providence, Rhode Island 02912, USA. james_head@brown.edu
Nature
|March 18, 2005
概括
最近的Mars Express图像揭示了热带和中度地区富含冰的冰川沉积物,这表明地质上最近的气候变化. 这些发现表明,未来的勘探任务可以使用可访问的冰储量.
科学领域:
- 行星科学 行星科学
- 冰川学的冰川学
- 火星地质地质学
背景情况:
- 火星大基上的碎片围表现出复杂的地质特征.
- 以前的研究已经表明火星上过去的冰川活动,但最近的活动不太了解.
研究的目的:
- 为了调查火星的Hellas和Olympus Mons地区最近的地质冰川活动的证据.
- 评估这些沉积物中的冰的组成和可访问性,以便在未来进行勘探.
主要方法:
- 分析来自火星快递轨道器的高分辨率立体相机 (HRSC) 图像.
- 对地形特征的解释,如碎片围,叶状特征和坑洞.
- 希腊东部的沉积物与奥林匹斯山脉山脉底部的沉积物进行比较.
主要成果:
- 识别了许多同心,叶状和坑状的特征,这些特征表明富含冰的粘性流和升华.
- 最近发现的富含冰的岩石冰川叠加在奥林匹斯山的旧冰川上.
- 在轴斜率增加的时期,在较低度地区出现反复的冰川活动的证据.
结论:
- 火星在地质上是最近的,在热带和中度地区经常出现冰川活动.
- 这些沉积物含有丰富的剩余冰,提供有价值的气候记录.
- 已识别的富含冰的沉积物是未来机器人和人类探索的可访问目标.
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