黏性土弱透水层压实作用:原理、技术及其水文地质意义

弱透水层与含水层相互作用是国际水文地质学界关注的热点问题,特别是黏性土弱透水层与孔隙含水层的相互作用。近年来,在自然沉积、过量开采地下水、现代化农业机械与建筑业重型机械应用等自然与人为活动影响下,黏土弱透水层会发生有效应力增加、孔隙结构变形和孔隙度减少、渗透性降低、溶解氧和贮水能力减少以及侧向和垂向排水等的压实作用,导致地下水污染、地面沉降等环境问题的发生。本文重点介绍了黏性土弱透水层压实作用的原理,分析了地下水系统中4种不同状态下沉积物压实与孔隙流体压力的关系,基于压实物理模拟和数值模拟两个方面对压实作用的研究方法与技术进行了系统总结,随后探讨了压实作用下黏性土弱透水层对地下水水量与水质的影响,并对此研究的发展趋势及其在地球科学、环境科学等研究领域的潜在应用提出了展望。

Compaction of clay aquitard: Principle,technology and hydrogeological significanc

The interaction between aquitard and aquifer is a global hot topic in the field of hydrogeology, especially the interaction between clay aquitard and pore aquifer. In the past few years, affected by natural and human activities such as natural deposition, excessive exploitation of groundwater, and use of modern agricultural and heavy construction machinery, clay aquitard can become compacted and result in property changes, including increase of effect stress, pore deformation, decreases of porosity, permeability, dissolved oxygen and water storage capacity, and lateral and vertical drainage. Nowadays, land subsidence and groundwater pollution caused by clay aquitard compaction have become important global environmental issues. In this paper, we introduce the theory of clay compaction, analyze the relationship between sediment compaction and pore liquid pressure under four different states in groundwater system, review the compaction study methods and technology based on physical simulation and numerical modeling, and discuss the effect of clay compaction on the water and groundwater qualities. The trend of aquitart research and its potential applications in Earth sciences and environmental sciences are also discussed.