永久土在覆盖的盐水下解
Yumin Wang1, Jin-Han Xie2, Wei Yang1,3
1Department of Energy and Resources Engineering, College of Engineering, Peking University, Beijing 100871, China.
Science advances
|March 28, 2025
概括
盐水侵入永久土会造成雷利-达西不稳定性,令人惊的是,在高雷利数下会导致稳定的融化. 这挑战了现有的模型,并表明永久土的融化速度比预期的要快.
科学领域:
- 地质物理学 地质物理学
- 环境科学 环境科学
- 流体动力学 流体动力学
背景情况:
- 永久土融化对当地环境和全球气候产生重大影响.
- 雷利-达西 (R-D) 不稳定性发生在盐水覆盖永久土时,由于密度差异,影响融化动态.
研究的目的:
- 研究雷利数 (R) 与盐水与永久土相互作用中的融化模式之间的关系.
- 开发理论模型,解释观察到的融化现象及其影响.
主要方法:
- 在不同的雷利数下对R-D不稳定性的实验研究.
- 对竞争的流体结构的分析:局部环流和横向混乱混合.
主要成果:
- 观察到指纹化前沿在低R和稳定的化前沿在高R,与预期相反.
- 确定了环流和混乱混合之间的相互作用,作为融模式的驱动因素.
- 提出了融化模式转变和指尺度演变的理论.
结论:
- 经典的质量运输理论低估了研发对流中的化速率.
- 指纹模式和加速的动态表明永久土的透速度更快.
- 这些发现与岩迁移,碳捕集和地下能量回收有关.
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