Hydrogéologie des séries sédimentaires de la dépression piézométrique du Gondo (bassin du Sourou) : Burkina Faso / Mali
- HAL (Le Centre pour la Communication Scientifique Directe)
Résumé
The Gondo Plain belongs to the Cenozoic intra-continental basins of sahelian Africa. It lies between Mali and Burkina Faso with an area of about 30 000 km². It has aquifer systems: an unconfined aquifer and a deeper confined one. The unconfined groundwater level shows a piezometric depression and the roof of the confined groundwater is more and more deep toward the centre of the Gondo basin. The present study deals in general with the natural context of the Gondo Plain and particularly with the Sourou Basin at Léry before dwelling on the lithology and the geometry of the aquifer system of the Gondo Plain. Then the results of the various investigations using an interdisciplinary approach (remote sensing, geophysics, major ions chemistry, isotopic geochemistry, pumping test modelling) allowed to better understanding of the groundwater recharge and their hydrodynamic working. The preferential recharge occurs under the Sourou reservoir and under the spreading cones of the border of Gondo basin. This recharge is up from 0,9 to 5 meters by year. A recharge model of the groundwater has been in permanent regime. This model takes into account exfiltration by evaporation and additional infiltration in the spreading cones of the border of the Gondo basin.
Mots-clés
Humanities, Geology, Forestry, Physics, Art, Geography