概括
火星的地面冰分布不均,在赤道稀少,在更高的度处丰富. 这表明,由于升华和扩散,冰在火星历史上向极地迁移.
科学领域:
- 行星科学 行星科学
- 地质物理学 地质物理学
- 天体生物学 天体生物学
背景情况:
- 火星上的地形特征表明了地质过程.
- 接近地表的材料可能含有大量的地面冰.
- 火星地面冰的分布对于理解行星进化和可居住性至关重要.
研究的目的:
- 为了调查火星地形的准粘性放松的证据.
- 为了确定火星地面冰的全球分布和特征.
- 了解控制火星历史上的冰再分配的过程.
主要方法:
- 对维京轨道卫星高分辨率图像的分析.
- 解释地形数据以推断准粘度放松.
- 在近地表面材料中的爬行变形的建模.
主要成果:
- 观察到地形形状的准粘性放松的证据.
- 地面冰的分布显示出强烈的度依赖性,在赤道上缺乏冰,在 +/- 30 度度的极点上富含冰.
- 滑动变形风格因度而异,可能是由于温度依赖的冰层风湿学.
结论:
- 火星地形的放松受地底冰的影响.
- 在火星较高的度上存在大量的地下冰储量.
- 在较低度的升华和扩散在整个火星历史中推动了极端冰的净运输.
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