Geology and Mineral Resources of Oyo State, South Western Nigeria

Oyo State lies in the south-western part of Nigeria. Underlain by three lithological units of the crystalline basement complex, comprising: (i) Migmatite-Gneiss Complex (quartzite, gneissic rocks); (ii) Low to medium grade metasediments (Green schists facies, namely quartz schist and mica schist). (iii) The Pan African Granitoids (older granites) which are syn to late tectonic intrusions. With these composite of rocks, Oyo State has various minerals ranging from metallic, non-metallic, to industrial minerals to various grades of gemstones. Prior discoveries make the northern portion of Oyo State to be predominantly underlain by complex pegmatite, which harbour a lot of gemstones ranging from Aquamarine, Tourmaline, Agate and industrial minerals like Tantalite, Marble, Talc and Granites of various forms. Later discoveries point to Ibadan axis where metallic minerals, e.g. gold, and gemstones like Aquamarine, Amethyst, Tourmaline, and industrial minerals like Tantalite and Sillimante, have been discovered in economic form. Geochemical explorations are being carried out as a follow up to the airborne geophysical survey that has been conducted by the Nigerian Geological Survey Agency, to actualize the mineralization of different minerals.