Use of Remote Sensing and GIS for Groundwater Potential Mapping in Crystalline Basement Rock (Sabodala Mining Region Senegal).
Detection of favorable zones for sustainable groundwater supply in terrains underlying by crystalline rocks needs to integrate two approaches: Remote Sensing and GIS. Landsat ETM+ images are processed by using ERDAS IMAGINE 9.2 and ASTER images by ArcGIS 9.3. Parameters controlling groundwater accumulation such as: rainfall, lineaments, lithology, slopes, and drainage network are evaluated in terms of 5 potential classes namely: very good potentials, good; moderate; low and very low potential and integrated in the GIS tool. The resulting map shows that 5% of the study area presents a very good groundwater potential and this part is mainly concentrated in the south part of the study area and on the MTZ, very low potentials constitute 13% of the area located essentially in the north part of the study area and particularly on granites. Combination of results generated by the GIS with NDVI and the borehole productivities shows that, generally good groundwater potentials are well correlated with high vegetal activities in dry season except in areas affected by forest fires which are frequent in the region. High borehole productivities (11.5 -30m3/H) are observed in zone presenting high groundwater potential resulting from the GIS tool and very low borehole productivities (0.6-2.5m3/H) are shown in the north part of the study area corresponding to the low and very low groundwater potentials. Good, moderate and low groundwater potentials represent respectively 18, 33 and 30% of the total investigated surface area. This integrated approach combining Use of RS, GIS and hydrodynamic parameters such as borehole productivities can contribute to improve Knowledge of groundwater resources investigation in context of hard rock aquifers of the south-eastern of Senegal and can reduce the high rates of failed wells. So, RS and GIS can be used as an efficient tools for assessing groundwater potential at large scale.
Auteur(s) : Moctar DIAW
Pages : 317-336
Année de publication : 2014
Revue : Nova Science Publishers
N° de volume : Chapiter 10
Type : Article
Statut Editorial : Revue
Mise en ligne par : DIAW Moctar