Development of a 3D geological and hydrostratigraphic model of the Agourai plateau (Morocco): insights into karst aquifer dynamics and structural framework

A comprehensive understanding of reservoir architecture in complex karst environments requires the integration of geological and hydrogeological data within three-dimensional modelling frameworks. This study presents the first 3D geological and hydrostratigraphic model of the Agourai Plateau in Morocco, developed using the Groundwater Modeling System (GMS). The model integrates a diverse set of datasets, including borehole logs, geological maps, geophysical interpretations, structural network analyses, and piezometric measurements.

This integrated modelling approach delineates the spatial extent of geological units and refines the structural framework of the study area, capturing the complexity of the karst system. Notably, the incorporation of piezometric data into the solid model enhanced the traditional geological model, enabling the generation of detailed piezometric surfaces and high-resolution hydraulic cross-sections. The model identifies eight distinct geological units, from the basement rock to the overlying aquifer formations, with the total groundwater storage volume of the karst aquifer estimated at 36.3 × 10⁹ m³.

In addition to mapping the distribution of major faults that control groundwater dynamics, the model provides new insights into subsurface flow patterns and highlights the role of abandoned quarry zones in influencing the aquifer system. This regional-scale model demonstrates the potential of integrated 3D modelling as a decision-support tool for the sustainable management and protection of groundwater resources in vulnerable karst regions