GEOCHEMICAL AND PETROGRAPHIC EVIDENCE OF BARROVIAN FACIES METAMORPHISM IN THE ISEYIN-OYAN-IBADAN SCHIST BELT, SOUTHWESTERN NIGERIA: IMPLICATIONS FOR PALEOPROTEROZOIC CRUSTAL EVOLUTION
GEOCHEMICAL AND PETROGRAPHIC EVIDENCE OF BARROVIAN FACIES METAMORPHISM IN THE ISEYIN-OYAN-IBADAN SCHIST BELT, SOUTHWESTERN NIGERIA: IMPLICATIONS FOR PALEOPROTEROZOIC CRUSTAL EVOLUTION
Isiaq Rofiat R.,Olatunji Akinade S,2 Authors,Mustapha Adedamola H.
Abstract
The Iseyin-Ibadan Schist Belt in southwest Nigeria, part of the Nigerian Basement Complex, displays Barrovian-type metamorphism typical of the Dalradian Supergroup of the Scottish Highlands; this study investigated the metamorphic basement south of this schist belt where Dalradian metamorphism was first reported, analyzing mineralogical composition and geochemical characteristics of quartz mica schist and muscovite garnet schist through field mapping, petrographic analysis, and whole-rock geochemistry, revealing greenschist to amphibolite facies metamorphic grade with assemblages like phengite-bearing muscovite, biotite, and almandine garnet, showing subtle compositional differences but striking mineralogy, particularly in muscovite and garnet concentrations, while an average Al2O3/TiO2 value (41.30) indicated a granitic source for the metasediments, and geochemical signatures, including major oxides, suggested mixed provenance and moderate weathering intensity.