概括
溶解的水显著加速-134在花岩融中的扩散. 这一发现表明,在含水的酸溶液中,化学过程平衡时间更快.
科学领域:
- 地质化学 地质化学
- 材料科学 材料科学 材料科学
背景情况:
- 了解地质融中的离子扩散对于地球化学建模至关重要.
- 以前的研究表明,干燥的花岩玻璃表现出缓慢的扩散率.
研究的目的:
- 为了研究溶解水对-134在花岩融中的自我扩散的影响.
- 量化扩散系数和激活能量的变化.
主要方法:
- 进行了放射性痕迹剂 (-134) 扩散实验.
- 实验是用6.1-6.3重量%溶解的H2O进行的.
- 扩散在700-800°C和2 kbar.时被测量.
主要成果:
- 在水的存在下,-134的扩散系数高出3-4个数量级.
- 扩散的激活能量约为20kcal/mol,明显低于干玻璃中的激活能量.
- 的扩散性遵循阿雷尼乌斯方程:D = 7.19 x 10(-5) exp (-19.52 x 10(3) /RT).
结论:
- 溶解的水极大地提高了岩石融中的离子流动性.
- 这种增强的移动性意味着水性融中的地质过程的化学平衡时间显著减少.
- 这些发现对了解各种地质环境中的融化行为具有重要意义.
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