Dr Léa Duran
Dept. of Civil, Structural & Environmental Engineering
Visualisation of Flow and Contaminant Transport Through Karst Aquifers
Keywords: Groundwater; Karst; 3D geological models; Rainfall-runoff modelling; Distributed modelling.
Carboniferous limestone is the primary aquifer rock in Ireland, coinciding with the most productive agricultural land, areas of most economic activity and major centres of population. Much of this carboniferous limestone is karstified and as such, the aquifer is at greater risk of contamination and flooding issues due to the rapid transit of water through them, the direct nature of their recharge via swallow holes, the lowland nature of much Irish karst and the thin layer of soil cover which typically overlays them. It is thus of great importance to increase the often poor understanding of these complex systems.
The primary aim of this research project is to develop a state of the art modelling methodology in order to make the groundwater flow and contaminant transport through karst aquifers more understandable by means of visual 3D models. This will be applied to a number of Irish karstic catchments in order to shed light on their hydrologic operation. A few modelling approaches have already been conducted on previous projects: one in the South Galway lowland based on a storm water pipe network, and another on the Bell Harbour system (SISKA approach with tools for 3D animations) as well as the Shanballymore catchment in north Cork.
Other models will be investigated as part of this research, among them MODFLOW-USG which has been developed to support a wide variety of structured and unstructured grid types and also includes a new Connected Linear Network (CLN) process to simulate the effects of multi-node wells, karst conduits, and tile drains.
In order to develop the modelling, the project implies the coordination and complementation of the ongoing iCRAG PhD studies in the groundwater spoke which are focusing on karst. The synthesis of these findings into usable modelling framework will help groundwater practitioners as well as the wider public to understand how flow and contaminant transport occurs. Hence, a strong focus of this work will be on the visualisation of karst systems by the models.
The research is conducted within the framework of the Irish Centre for Research in Applied Geosciences (ICRAG). iCRAG is funded under the SFI Research Centres Programme and is co-funded under the European Regional Development Fund.
Project Mentor: Prof. Laurence Gill