月球样本的元素组成和年龄,采用非破坏性马射线光谱学
概括
这项研究使用马射线光谱测量了岩石放射性,揭示了,和的度. 这些发现有助于估计分析的岩石样本的气体保留和宇宙射线暴露年龄.
科学领域:
- 地质化学 地质化学
- 核地质物理学 核地质物理学
- 宇宙化学 宇宙化学
背景情况:
- 地质样本中的放射性对于理解它们的形成和历史至关重要.
- 地球上的岩石和石表现出不同的元素组成,影响它们的放射性特征.
研究的目的:
- 用玛射线光谱测量来确定晶体岩石,石和细质物质的放射性.
- 量化关键放射性同位素 (K,Th,U) 和宇宙原核酸的度.
- 为了估计岩石样本的气体保留和宇宙射线暴露年龄.
主要方法:
- 利用低背景马射线光谱系统进行精确的放射性测量.
- 确定了包括-40,-232,-238和宇宙同位素在内的特定核化物.
- 结合同位素度与稀有气体数据用于年龄估计.
主要成果:
- 测量K,Th和U度的范围分别为480-2550 ppm,1.01-3.30 ppm和0.26-0.83 ppm.
- 观察到的和含量与陆地玄武岩相似,含量接近混凝土的值.
- 在岩石表面检测到低能核反应产物的度梯度.
结论:
- 元素组成表明分析的岩石的混合起源或特定的地质过程.
- 据估计,气体保留年龄在2.200亿至3.2亿年之间.
- 估计的宇宙射线暴露年龄在3.4亿年至3.4亿年之间,这表明长时间地表暴露.
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