Two numerical simulations using Feflow® software were conducted to demonstrate the utility of geophysical data to accurately determine groundwater levels and provide additional data to the groundwater modelling community to improve the model’s accuracy. One simulation is based on regional piezometric data, and the other uses geophysical data acquired through transient electromagnetic (TEM), electrical resistivity (ERT), and ground-penetrating radar (GPR) surveys. After both numerical analyses, the root mean square errors (RMS) obtained from the piezometric data and the multiple geophysical techniques to confirm the correlation between observed and simulated water levels were similar at 3.81 m and 2.76 m, respectively. Through a discrete modelling approach, this study shows that groundwater levels estimated using geophysical tools and methods and those determined by direct observation are comparable. In addition, before the 3D numerical flow model, a 3D geological model was built to fully represent this highly complex, heterogeneous, and anisotropic hydrological environment of the Saint-Narcisse moraine glacial deposits in eastern Mauricie, Québec. This stratigraphic reconstruction with Leapfrog software was necessary to provide a more detailed and realistic representation of this complex aquifer system. This study illustrates how geophysical data can complement direct observations to provide additional hydraulic information to hydrologic modellers. Geophysical surveys provide an extensive set of soft data that can be leveraged to improve groundwater flow models and determine water-table heights, particularly in areas characterized by limited direct piezometric information.
Presenter Name
Y
Presenter Surname
Lévesque
Area
Canada
Conference year
2023