HARD ROCKS AQUIFER PROPERTIES ESTIMATION AND MAPPING THE OPTIMAL DEPTH OF WELLS TO DRILL IN DIVO-GUITRY AREA, SOUTHERN COTE DIVOIRE

Pressures on water resources are intensifying in several regions of Cote dIvoire, including the Divo-Guitry fissured basement area. However, data for a good understanding of the hydrogeological environment remains scarce. This study used simple exploitation boreholes data and geological maps to assess the geometric and hydrodynamic properties of the Divo-Gutry aquifer. The study took place on biotite metatonalite (MTR), biotite metagranodiorite (MGDR) and biotite metagranite (MGR) rocks. Thus, the statistical analysis of the borehole parameters revealed that the largest values of total depth (Pt) of boreholes have a stronger occurrence on the MGR, where the largest thicknesse s of saprolite are more observed. On the contrary, in areas where thin saprolite thicknesses are more present (on the MTR), the largest borehole lengths below the base of the saprolites are noted. This is the case for the occurrence of the highest instantaneous discharges