Groundwater Flow Characterization in Kandi Basin (Benin, West Africa): a Combined Classic Hydrogeological and Isotopic Approach

International Symposium on Isotope Hydrology: Revisiting Foundations and Exploring Frontiers - CN225

Contribution ID: 79 Type: Poster

GROUNDWATER FLOW CHARACTERIZATION IN KANDI BASIN (BENIN, WEST AFRICA): A COMBINED CLASSIC HYDROGEOLOGICAL AND ISOTOPIC APPROACH

Classic hydrogeological and isotopic data of surface and groundwater were used to understand the ground- water flow patterns in the transboundary Iullemeden basin in its Benin’s part known as Kandi basin.Classic hydrogeological approach helped generate a piezometric map which shows that groundwater circulation in the basin is basically from the southern toward the northern of the basin, following the geomorphology, with a groundwater divide corresponding to the horst of Gbezé-Lété from which groundwater flows diverge. Tri- tium data indicate that groundwater in the basin recharged from post nuclear period (about 1965) to recent period. A combined use of 18O and 3H helped detect regions located in the northern basin where relatively ancient groundwaters dischage into sota river. Caborn-14 data show that the most recent groundwaters are found basically in the southern basin and the relatively ancient groundwaters are found in the northern basin around Sakaoun and Garoutedji townships. This quite logical organisation of groundwater age pointed out by isotope techniques confirms the groundwater flow parttern indicated by the obtained piezometric mapin the Kandi basin.

Primary author: Mr KPEGLI, Kodjo Apelete Raoul (Laboratory of Applied Hydrology, University of Abomey-- Calavi, 01 B.P. 4521 Cotonou, Benin.) Co-authors: Mr ALASSANE, Abdoukarim (Laboratory of Applied Hydrology, University of Abomey-Calavi, Cotonou, Benin); Mr MAMA, Daouda (Laboratory of Applied Hydrology, University of Abomey-Calavi, Cotonou, Benin); Mr DOVONON, Firmin Leonce (Directorate of Water Resources (DGEau), Cotonou, Benin); Mr ZOUARI, Kamel (Laboratory of Radio-Analysis and Environment, National Engineering School of Sfax, Tunisia); Mr BOUKARI, Moussa (Laboratory of Applied Hydrology, University of Abomey-Calavi, Cotonou, Benin) Presenter: Mr KPEGLI, Kodjo Apelete Raoul (Laboratory of Applied Hydrology, University of Abomey-Calavi, 01 B.P. 4521 Cotonou, Benin.)

Track Classification: Groundwater Resources, Age Dating, and Geochemical Evolution