在过去的百万年里,碳状石石经历了流体流动
Simon Turner1, Lucy McGee2, Munir Humayun3,4
1Department of Earth and Environmental Sciences, Macquarie University, Sydney, NSW 2109, Australia. simon.turner@mq.edu.au.
概括
原始石显示了最近流体流动的证据, 这表明它们的母体可能仍然含有冰,影响我们对太阳系早期过程的理解.
科学领域:
- 宇宙化学
- 星球科学
- 地质化学
背景情况:
- 碳状石是太阳系的原始物质.
- 这些石对于了解地球的水供应至关重要.
- 早期流体流 (<400万年) 在石母体上已知.
研究的目的:
- 在石母体上调查最近的流体流动事件.
- 分析碳酸中的短寿命同位素变化.
- 为了确定与宇宙射线接触相对的迁移时间.
主要方法:
- 分析短寿命的同位素 (234-U,238-U,230-Th).
- 测量过量的 (234-U/238-U和238-U/230-Th).
- 流体流动时间尺度与宇宙射线暴露年龄的比较.
主要成果:
- 检测到超过234超过238和238超过230.
- 这些过量表明流体移动的U6+离子在过去几十万年内移动.
- 在一些石中,这种流体流动比它们从母体喷射出来的时间更近.
结论:
- 最近的流体流,可能是由撞击加热,发生在石母体.
- 这种流体活动发生在冰融化后,
- 这些发现为早期太阳系天体的热史和组成提供了新的见解.
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