Geospatial modeling for groundwater potential zoning using a multi-parameter analytical hierarchy process supported by geophysical data

Abstract

Groundwater plays a crucial role in Hungary sustaining ecosystems and meeting the growing demand for freshwater to fulfill domestic and agricultural needs. This study employs the analytical hierarchy process (AHP) methodology to delineate groundwater potential zones in the Debrecen area, Hungary. To ensure the robustness and reliability of the potential zoning, geophysical data are utilized for validation purposes. In the AHP modeling seven groundwater conditioning factors are integrated, including geology, topography, slope, land use/land cover, precipitation, drainage density, and lineament density. The integration of the normalized weights for each factor identified three groundwater potential zones (GWPZs) assigned as moderate, high, and very high potential. The result of the AHP model is further validated with geophysical data of gravity and wireline logging. Gravity data is subjected to spectral analysis and forward modeling to map the lineaments and detect the thickness of the sedimentary sequences. The forward modeling indicated that the thickness of these sequences varies between 1.25 and 2.7 km, with a deep local basin delimited by normal faults situated in the eastern part of the study area. Additionally, the analysis of the well-logging data using the Csókás method provided a continuous estimation of petrophysical and hydrogeological parameters along the main hydrostratigraphical units. Accordingly, a high and uniform distribution of hydraulic conductivity is observed in the eastern part of the study area due to the presence of coarse-grained incised valley deposits. The results of geophysical modeling showed a close agreement with that of AHP models. This interdisciplinary approach advanced the mapping of potential groundwater zones and provided valuable insights into the hydrogeological characteristics of the groundwater aquifers in the Debrecen area.