Hydrogeology and Hydrogeophysics Research Unit

The Laboratory for Applied Geology and Hydrogeology (LTGH) conducts research on hydrogeology, hydrogeochemistry and applied geophysics, with special emphasis on hydrogeophysics. For quantitative aspects, our research focuses on groundwater resources, groundwater exploitation and sustainability, and this in relation to climate and specific groundwater use practices, both in Flanders and in developing countries.

From a qualitative point of view, the basic natural quality of aquifers is studied. Against this natural background, pollution is studied, focusing in particular on diffuse pollution (mostly from nitrates). LTGH has been involved in several European projects related to the natural basic chemistry of groundwater, which have supported the development of the EU Groundwater Directive.

Research on nitrate distribution in groundwater in Flanders has laid the foundation for the Flemish policy on nitrate pollution of groundwater. LTGH has been investigating the relationship between fresh and salt water in the Belgian coastal zone (i.e. saltwater intrusion) since 1960 and is still involved in research on this fascinating phenomenon, also abroad (e.g. Libya, Palestine, Tanzania, Vietnam). Geophysical prospecting is extensively applied for research on saltwater intrusion, as well as in cases of pollution and geological characterization. LTGH is active in the application and development of innovative geophysical imaging techniques with a special emphasis on the geophysical monitoring of natural processes and active experiments (e.g., heat tracing experiments, monitoring of volcanic hydrothermal systems).

In recent years, LTGH has paid increasing attention to Africa, where groundwater exploitation, pollution and the problem of sustainability of groundwater resources are even more directly of vital concern than in the industrialized world. Several doctoral theses and dissertations on African groundwater sustainability problems have recently been completed, with many more in progress.

News and events

25-04-2024 – Meet the PhD Jury – Carlos Duque – University of Granada

On the occasion of the PhD defense of Marieke Paepen a ‘meet the PhD jury’ activity with Carlos Duque from the University of Granada will be organized. The seminar will start by a public lecture titled ‘Heat as a tracer in the study of groundwater-surface water interaction’, followed by an open discussion. After the seminar, interested PhD students will get the opportunity to meet in person with Carlos Duque to discuss their own research. Interested students can register in advance (email to Thomas.hermans@ugent.be) and we will set a planning for 1-to-1 discussion.

When: 25th of April, 2024 from 3:30pm to 5pm  

Where: Valère Billiet, S8 (Campus Sterre)

Seminar abstract

During the last few decades, the study of groundwater and surface water interaction has gained prominence in hydrological research. The exchange of water between aquifers and surface water bodies triggers chemical reactions and impacts biological activity, expanding this topic to a multidisciplinary level. Despite the increased interest, several persistent challenges hinder research on these processes: the heterogeneity of the interaction between groundwater and surface water, the difficulty of upscaling measurements, the movement of water exchange areas depending on groundwater and surface water levels, and the difficulties in detecting flow that occurs underwater. Often, this requires multiple measurements to characterize natural systems, which also means increased research expenses. In this context, the use of temperature offers a quick and cost-effective alternative for increasing the number of measurements that can be collected. The application of heat as a tracer has undergone significant evolution in measurement collection systems, modeling options, and real-case scenario applications. However, there are still challenges to solve, as heat is not a perfect tracer and certain parameters in assessing heat transport remain rarely quantified. In this talk, I will provide a brief overview of the evolution in methods and applications of using heat as a tracer for studying groundwater-surface water interaction, drawing from my own experiences across various natural settings and the associated challenges.

Bio Carlos Duque

Carlos Duque completed his Ph.D. at the University of Granada in the study of coastal aquifers and saltwater intrusion problems in 2009. After this, he researched on groundwater-surface water interaction using heat as a tracer, stable isotopes of water and numerical modelling at the University of Copenhagen and the University of Oslo as a postdoc. In 2015, he was granted a Marie Curie International Outgoing Fellowship for the study of submarine groundwater discharge at the University of Delaware using seepage meters, groundwater modelling and radioactive tracers. In 2017, he was selected as Assistant Professor with Tenure at Aarhus University and in 2020 he was appointed Associate Professor position (20 %) at the University of Oslo, a position in which he is still active. In 2022 he was granted a Maria Zambrano Senior at the University of Granada where he is currently leading four research projects on topics related to managed aquifer recharge and freshwater reserves in coastal aquifers. 

The research of Carlos Duque has been oriented to develop methodologies tackling the challenges that natural systems bring. This includes the spatial heterogeneity of hydraulic properties, irregular groundwater flow paths, the differences in results when working at variable scales, and the chemical processes triggered by the interaction of different chemical signatures in groundwater. Using different sets of hydrogeological tracers and studying multiple natural settings along various regions of the world, his knowledge of technologies and his understanding of aquifer systems have allowed him to develop innovative viewpoints and new applications in the study of groundwater-surface water interaction, submarine groundwater discharge, and saltwater intrusion.  

29-03-2024 – Fieldwork in Iceland

A team from Ghent University and ULB is back on the field in Iceland, for the second part of Lore Vanhooren’s PhD. In the first part, some repairs were done on the measuring equipment at the Reykjanes geothermal field, which has been monitored for 1.5 years (!) with Electrical Resistivity Tomography (ERT) and Fiber Bragg Grating (FBG). The team is currently on site at the Strokkur Geyser to conduct ERT and seismic measurements, with the aim of imaging the geyser’s eruption cycle. Due to the busy tourism, they are forced to work at night, which has already produced beautiful images!

27-03-2024 – Geology in the Picture special lecture – Prof. Jef Caers – Stanford University

The 6th edition of the lecture series “Geology in the Picture” took place in the Aula of Ghent University. It was our pleasure to welcome Prof. Jef Caers (Stanford University, USA). His talk was not only about how artificial intelligence can accelerate mineral exploration but also about the crucial role of human intelligence (and geologists!) in the process, sustainability, social acceptance of mining activities and geopolitics.

20-12-2023 – Christmas market

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The highlight of the day was definitely the roller skating

To finish the year strong and with joy, Prof. Dr. Ir. Thomas Hermans and his team enjoyed a festive day at the Christmas market in Ghent. We all wish you a prosperous year ahead with lots of exciting discoveries!

1-12-2023 – SWIM conference

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On December 1st, Linh Pham Dieu, Diep Cong-Thi and Marieke Paepen attended the first Saltwater intrusion Symposium hosted at PWN (The Netherlands). Together with Dutch, German, and Italian colleagues they enjoyed a day full of interesting presentations and discussions on modeling, geophysics, and solutions to prevent salinization. All three also got the opportunity to present the latest advancements of their work.

27-11-2023 – living lab approved on Ardoyen campus

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More than ever, innovation and ambition are key when planning new projects. This influence is also clear at Ghent University. In the context of the climate plan, funding can be requested to set up a living lab. This is a collaboration between researchers, students and policy staff to contribute to the sustainable development of the campus. A project was recently approved to carry out a feasibility study for an aquifer thermal energy storage system (ATES) on the Ardoyen campus. ATES is a green alternative to provide both heating and cooling to buildings. However, on campus there is a poorly permeable aquifer, which means there is uncertainty regarding the feasibility. However, if the outcome of the study is positive, ATES will be able to make a significant contribution to the future green energy mix on the Ardoyen campus.

9-10-2023 – Wouter Deleersnyder defends his PhD thesis

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On October 9, Wouter Deleersnyder successfully defended his PhD thesis “Improving Airborne Time-Domain Electromagntic Imaging with Applications to Groundwater Salinity Mapping”. Congratulations!
Wouter will continue his research on airborne EM data, geophysical inversion, and uncertainty analysis in the coming year as a postdoctoral researcher.