Advancing Lineament Analysis and Hydrogeological Assessment of the Bou Arada-El Aroussa Aquifer System using Remote Sensing, GIS, and Machine Learning

Based on a multidisciplinary approach, the present research investigates lineaments as surface expressions of deep crustal structures, providing key insights into structural characteristics, mineral deposits, hydrodynamic functioning of the aquifer system and the origin and migration pathways of water bodies. It also emphasizes the role of faults and fractures in enhancing permeability and facilitating groundwater recharge conditions. This study analyzes the lineaments crossing the Bou Arada-El Aroussa (BAEA) plain in the Northern Atlasic domain of Tunisia, using remote sensing, GIS, and machine learning to assess their spatial distribution and hydrodynamic impact on aquifer recharge. Geological maps and a pre-processed Landsat 8 OLI/TIRS image served as the basis for lineament extraction and analysis, utilizing PCA, band ratio and composite imaging. Automatic identification yielded 747 to 839 lineaments, while 730 were digitized from geological maps. Machine learning techniques, using Scikit-learn and SciPy, made it possible to classify the entire lineament data into three Clusters based on equivalent orientations and lengths. This highlights distinct zones of fracture density associated with major tectonic structures and fault reactivation. It has been demonstrated that groundwater flow and aquifer recharge are significantly influenced by NW-SE, E-W, and N-S oriented lineaments. The high density of NW-SE and N-S lineaments between Koudiet Sidi Barka and Jebel ER Rihan plays a major hydrogeological role, ensuring rapid infiltration of rainfall into the Bou Arada-El Aroussa aquifer system. In contrast, E-W lineaments in the Bou Arada trough act as conduit-barriers, influencing regional groundwater dynamics. The impact of the aforementioned lineaments on the studied aquifer system hydrodynamics is however supported by the piezometric map, which reveals the mains recharge areas are located at the foot of Jebel Er Rihan, Koudiet Sidi Bakar, Jebel Bessioud, and Jebel Er Rmil. The findings of this investigation provide reliable information for the sustainable management of groundwater resources within fractured aquifer systems, particularly under semi-arid conditions.