RMZ – MATERIALI IN GEOOKOLJE

The groundwater potential evaluation at industrial estate Ogbomoso, ...369tite (Ajibade et al., 1988). The rockgroups in the area include quartzitesand gneisses (Ajibade et al, 1988).Schistose quartzites with micaceousminerals alternating with quartzofeldsparthicones are also experiencedin the area. The gneisses are the mostdominant rock type. They occur asgranite gneisses and banded gneisseswith coarse to medium grained texture.Noticeable minerals includequartz, feldspar and biotite. Pegmatitesare common as intrusive rocksoccurring as joints and vein fillings(Rahaman, 1976; Ayantunji, 2005).They are coarse grained and weatheredeasily in to clay and sand-sizedparticles, which serve as water-bearinghorizon of the regolith. Structuralfeatures exhibited by these rocks arefoliation, faults, joints and microfoldswhich have implications on groundwateraccumulation and movement(Ayantunji, 2005).Figure 1b. The hydrogeological domains of Nigeria (extracted from MacDonald &Davies, 2000).RMZ-M&G 2012, 59