Mega-scale groundwater systems

地下水是维持生命的重要资源，为大约1000万加拿大人、地表水和生态系统提供水。我研究了区域（10公里）到大陆（1000公里）尺度的地下水系统，我称之为“超大尺度”。研究超大规模的地下水系统是罕见的，但对于地球科学和工程界出现的一些重要的基础和应用问题是必不可少的。这些问题包括地球渗透性的分布、地下水位的性质和地下水排放以缓冲海洋酸化的潜力。拟议的研究侧重于当代的超大规模地下水系统，并将使用各种基于现场的工具和计算机模型。在这个资助期间，我的核心研究问题是：1)上地壳的渗透率分布是什么？ 2)我们能否更好地量化地下水位和地下水中溶解的二氧化碳到海洋的通量？这些问题将在5名本科生、2名硕士生、1名博士生和1名博士后的研究中通过4个可检验的假设进行检验。总的来说，这些研究将1)更好地定义渗透率的分布，这将导致地下水被包括在更多的水文、气候和陆地表面模型中；2)表明地下水可以在大陆尺度上进行研究，以回答紧迫的地球科学问题。此外，渗透率分布显著影响地质固碳、核废料库和页岩气勘探的可行性和安全性。该研究项目将维护和建立加拿大在这一重要的大型地下水系统领域的形象，特别是在水资源成为全球关注的重要问题之际。

Groundwater is a crucial life-sustaining resource that supplies water to ~10 million Canadians, surface waters and ecosystems. I examine groundwater systems at regional (10s km) to continental (1000s km) scales, which I refer to as 'mega-scale'. Examining mega-scale groundwater systems is rare yet essential for a number of important fundamental and applied problems have emerged in the geoscience and engineering communities. These problems include the distribution of permeability in the earth, the nature of the water table and the potential for groundwater discharge to buffer ocean acidification. The proposed research focuses on contemporary, mega-scale groundwater systems and will use a variety of field-based tools and computer models. During this grant period, my core research questions are: 1) what is the distribution of permeability in the upper crust and 2) can we better quantify the water table and the flux of carbon dioxide dissolved in groundwater to the ocean? These questions will be examined through four testable hypothesis in studies conducted by five undergraduate students, two MSc students, one PhD student and one postdoctoral fellow. Overall these studies will 1) better define the distribution of permeability which will lead to groundwater being included in more hydrologic, climate and land-surface models and 2) show that groundwater can be examined at continental scales to answer pressing geoscience problems. Additionally, the distribution of permeability significantly impacts the viability and safety of geological carbon sequestration, nuclear waste repositories and shale gas exploration. This research program will maintain and build Canada's profile in this critical field of mega-scale groundwater systems, especially as water resources emerge as a significant global concern.