Geology and Geochemistry of Iroko-Granites Southwestern Nigeria: Implication on Provenance


  • Olusola A. OlaOlorun Department of Geology, Ekiti State University Ado-Ekiti, Nigeria
  • Segun Akinyemi Department of Geology, Ekiti State University Ado-Ekiti, Nigeria
  • Ayomide J. Oluwaleye School of Geosciences, University of the Witwatersrand, Johannesburg, S.A.
  • Joseph Agbemuko Department of Geology, Ekiti State University Ado-Ekiti, Nigeria



The geology, geochemistry of Iroko-granites have been studied and reported in this paper. The study area has been described as of Archaean-EarlyProterozoic terrain underlain by migmatite-gneiss-quartzite complex with supracustal rocks. Large number of granites which outcrops in Iroko-Ekiti represent a typical occurrence of granitoids sporadically distributed in thebasement and are known to belong to the Older Granite suites, which are attributable to the Pan-African Orogeny (750± 150Ma). The rocks occur,mostly as flat and low lying within sparse vegetation. Structures common on and around the outcrops include quartz vein, veinlets, pegmatite dykes which trend North-south, discrete exfoliated surfaces and xenoliths of older rocks. This study reveals that the granites belong to calc-alkalic suites,demonstrate metaluminous nature, and exhibit characteristics of I-type granites. The granite is a distinctive type in that it is relatively highly potassic, has high FeO/(FeO + MgO) ratio, and high average Zr (299.75ppm)concentration with other high field strength elements. The trace elements study implicates pronounced fractional crystallization during evolution of the granites and thus petrogenetically discriminates as Syn-collision provenance.


Iroko-granites; granitoids; metaluminous; fractional crystallization; Syn-collision


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How to Cite

OlaOlorun, O. A., Akinyemi, S., Oluwaleye, A. J., & Agbemuko, J. (2020). Geology and Geochemistry of Iroko-Granites Southwestern Nigeria: Implication on Provenance. Journal of Geological Research, 2(3), 56–63.


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