Analysis of the Hydrodynamic Properties of the Fissure Aquifers of the Black Volta Catchment in Ivory Coast

Abstract

The present study aims to analyze the productivity of aquifers in the Ivorian part of the Black Volta basin. It proposed to characterize the intrinsic hydrodynamic parameters of the productivity and to know the influence of these on the productivity of the drillings. The hydraulic parameters of the catchment structures and the pumping test sheets were used to determine the hydrodynamic properties through a methodological approach integrating Cooper Jacob's empirical formulas and automated calculations using the Pumping Interpretation Assistance Tool (OUAIP). A standardized principal component analysis (ACPN) was used to analyze the correlation of the different parameters. The results obtained range over several orders of magnitude. The values of the specific flow oscillate between 0. 01 and 4.87m²/h while the transmissivity varies between 1.25E-07 and 7.34E-03 m².s-1. As for the critical flow, it is between 0.869 and 26.6 m3/h. These values indicate that the aquifers generally have low specific flow rates, but fairly good transmissivity. The Normalized Principal Component Analysis (ACPN) allowed to highlight the different productivity factors of the aquifers in the region: water level variation, and hydraulic role of fractures. It also showed the influence of the depth of the drilling on productivity. These results contribute to the knowledge of the structure and hydrodynamic functioning of the aquifers of the basin basement. They show the structural links between hydrodynamics and aquifer productivity.