TITLE:
Lithological and Hydrodynamic Controls on Borehole Productivity in Basement Aquifers of the Poro Region, Northern Côte d’Ivoire
AUTHORS:
Koffi Yao Honoré, Kpan Oulaï Jean-Gautier, Kouadio Assoué Sylvestre, De Lasme Omer Zéphir
KEYWORDS:
Basement Aquifer, Fractured Granite, Transmissivity, Specific Capacity, Boreholes, Poro, Côte d’Ivoire
JOURNAL NAME:
International Journal of Geosciences,
Vol.17 No.10,
October
30,
2026
ABSTRACT: This study investigates the lithological and hydrodynamic controls on borehole productivity in basement aquifers of the Poro Region, northern Côte d’Ivoire. The aim is to identify the factors controlling yield contrasts and borehole drying risks in fractured crystalline terrains. The methodology combines borehole technical sheets, metre-by-metre descriptions of drill cuttings, lithological logs, pumping-test interpretation using the Cooper-Jacob recovery method, and statistical analyses of hydrogeological parameters. The results show a typical weathered-fractured basement architecture, including lateritic duricrust, weathered clays, granitic saprolite and fractured granite. First water strikes mainly occur within fractured granite, with several of water inflows recorded between 27 and 60 m depth. Boreholes have an average depth of 79 m, an average exploitation yield of 8.09 m3/h, an average specific capacity of 0.25 m3/h/m and an average transmissivity of 2.38 × 10−4 m2/s. Correlations and normalized principal component analysis indicate that productivity is primarily governed by transmissivity, hydraulic conductivity and specific capacity, whereas simply drilling deeper does not guarantee higher yields. These findings support the need for structural and geophysical targeting of connected fractures, together with long-term piezometric and hydrochemical monitoring.