火星上的阿塔巴斯卡谷 (Athabasca Valles):一个岩覆盖的道系统
W L Jaeger1, L P Keszthelyi, A S McEwen
1Astrogeology Team,U.S. Geological Survey, Flagstaff, AZ 86001, USA. wjaeger@usgs.gov
Science (New York, N.Y.)
|September 22, 2007
概括
火星上的阿塔巴斯卡山谷,曾经被认为是水洪水雕刻的,实际上被最近火山爆发的岩流所覆盖. 这些岩流也解释了该地区明显的冰特征.
科学领域:
- 行星科学 行星科学
- 火山学 火山学是一门学科.
- 地质地质地质地质地质地
背景情况:
- 火星上的阿塔巴斯卡谷是一个突出的出流道系统.
- 以前的解释表明,灾难性的水灾造成了这些运河.
- 表面材料的存在一直是理解火星地质历史的关键焦点.
研究的目的:
- 调查阿塔巴斯卡山谷的表面组成和地质过程.
- 重新评估Athabasca Valles和Cerberus Palus中的特征的起源.
- 了解火山与河流过程在火星运河形成中的普遍性.
主要方法:
- 来自高分辨率成像科学实验 (HiRISE) 摄像机的高分辨率图像的分析.
- 在Athabasca Valles和Cerberus Palus内地表特征的地质解释.
- 观察到的特征与已知的火山和河流地形进行比较.
主要成果:
- 阿塔巴斯卡谷被一层薄薄的凝固岩覆盖.
- 岩源于裂喷发,淹没了道.
- 以前被解释为冰的特征被证实是火山起源的.
- 类似的火山过程可能对其他火星河流道的表面材料负责.
结论:
- 阿塔巴斯卡山谷的形成主要归因于最近的火山活动,而不仅仅是水灾.
- 岩流是一个重要的地质过程,塑造了火星的道系统.
- 这些发现表明,重新评估火星上潜在的古代洪水遗址的表面成分是必要的,因为岩可能比以前假设的更广泛.
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