在多孔岩石中扩散是异常的.
Ashish Rajyaguru1, Ralf Metzler2,3, Ishai Dror1
1Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel.
Environmental science & technology
|May 13, 2024
概括
在岩石和沉积物中的地表分子扩散并不总是Fickian. 异常扩散,以长期尾巴为特征,是常见的,需要先进的分析方法来准确预测.
科学领域:
- 地质化学 地质化学
- 环境科学 环境科学
- 物理化学 物理化学
背景情况:
- 分子扩散对于影响水化学的地下过程至关重要.
- 传统模型假定Fickian扩散,这可能不能准确地代表现实世界的条件.
研究的目的:
- 在岩石样本中调查和证明异常 (非Fickian) 扩散.
- 将观察到的扩散行为与经典的Fickian模型进行比较.
主要方法:
- 在两个月内对分子扩散的实验测量.
- 分析了5个石灰和多洛米特岩石样本中的扩散.
- 连续时间随机步行框架的应用.
主要成果:
- 在所有岩石样本中观察到异常扩散行为.
- 扩散显著偏离了Fickian预测.
- 连续时间随机步行分析揭示了极端长时间的跟踪追踪器的进步.
结论:
- 异常扩散是地下异质多孔材料中无处不在的现象.
- 在地下区域的扩散驱动过程需要使用非Fickian扩散模型.
- 需要先进的分析工具来准确建模地下运输.
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