在SNC石中的水:火星水球的证据
H R Karlsson1, R N Clayton, E K Gibson
1Planetary Science Branch, National Aeronautics and Space Administration, Johnson Space Center, Houston, TX 77058.
Science (New York, N.Y.)
|March 13, 1992
概括
在火星石 (SNC) 中发现的水是外星的. 氧同位素分析揭示了不同的水库,这表明火星可能缺乏板块构造学,这是保持水和岩石组成分离的关键因素.
科学领域:
- 行星科学 行星科学
- 地质化学 地质化学
- 天体生物学 天体生物学
背景情况:
- 谢尔戈蒂-纳克拉-查西尼 (SNC) 石被认为起源于火星.
- 这些石含有大量的水 (0.04-0.4%的重量).
- 确定这种水的起源和性质对于了解火星历史至关重要.
研究的目的:
- 为了调查SNC石中的水的起源.
- 为了确定水是否与其宿主岩石处于同位素平衡.
- 推断对母体,可能是火星上的地质过程的含义.
主要方法:
- 在SNC石中对水和宿主岩石进行氧气同位素分析.
- 对同位素特征进行比较,以区分陆地和外星的水.
- 评估不同行星储库之间的同位素平衡.
主要成果:
- 在SNC石中的一部分水被证实是外星的.
- 这种外星水被发现与宿主岩石没有氧气同位素平衡.
- 这表明形成了两个不同的氧同位素储库 (石化层和水层).
结论:
- SNC石中含有外星水,它没有与宿主岩石同位素相互作用.
- 不同的石层和水层氧气同位素储库的存在表明缺乏普遍的混合.
- 如果火星是母体,这种缺乏平衡可能归因于板块构造学缺乏.
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