Geochemical characterization of quartzite around Owu Ile, Southwestern, Nigeria

The quartzites of Owu-Ile, situated within the southwestern sector of the Nigerian Basement Complex, form part of the Pan-African orogenic domain and record a complex polycyclic metamorphic history. This study integrates geological mapping, petrography, and whole-rock geochemistry to elucidate the compositional and tectono-thermal evolution of these quartzites. The rock assemblage is predominantly comprised of quartzite, migmatite-gneiss, syenite, and pegmatite. Quartzites exhibit both massive and foliated fabrics, with granoblastic textures and modal compositions dominated by quartz (average. 90.56%), accompanied by muscovite (5.69%), opaque minerals (2.75%), and trace accessory phases. Optical petrography reveals pervasive undulose extinction, subgrain development, and microfractures, indicating significant post-depositional deformation and recrystallization. Geochemically, the quartzites are compositionally mature, with SiO₂ contents ranging from 95.61–97.66 wt.% (mean: 96.49 wt.%), and systematically low concentrations of TiO₂, Al₂O₃, Fe₂O₃, K₂O, and other major oxides. Trace element signatures (e.g., Ba, Zr, Cr, Rb) are depleted (<30 ppm), and immobile element ratios (TiO₂/Zr) plot within the felsic field, implicating derivation from reworked continental crustal sources, notably surrounding migmatitic and granitic lithologies. Collectively, the petrochemical data support the classification of the Owu-Ile quartzites as quartz arenites of sedimentary origin, metamorphosed under greenschist to lower amphibolite facies, and tectonically reworked during Pan African orogeny. Their purity and compositional uniformity highlight their potential for industrial utilization, particularly in silica-based applications.