relation: http://eprints.covenantuniversity.edu.ng/18264/
title: METAMORPHIC EVOLUTION OF A METABASITE DYKE FROM OGBAGI AKOKO  AREA, SOUTHWESTERN NIGERI
creator: Oziegbe, Ehitua Julius
creator: Ocan, O.O.
creator: Adetunji, A.
creator: Oziegbe, O.
subject: QH Natural history
subject: QH301 Biology
subject: QR Microbiology
description: Petrography, mineral chemistry and whole rock analyses were conducted on a metabasite dyke hosted by pelitic  gneiss (metapelite) in Ogbagi Akoko area with the aim of determining its metamorphic evolution. The dyke is  about 40 cm wide and traceable for some meters along strike. It has a discordant contact relationship that is  pencil sharp with the host pelitic gneiss and lack any internal fabric. The mineral assemblage includes: garnet +  biotite + plagioclase + quartz + orthopyroxene + K-feldspar + ilmenite, with apatite occurring as an accessory  mineral. Plagioclase has anorthite content of about 76 (An ) suggesting bytownite (An Ab Or ) while garnets 76 76 24 0  are poikiloblastic almandine-pyrope rich with XFe of 0.73-0.75. Orthopyroxene has a composition of  Wo En Fs suggesting hypersthene that is depleted in Ca. The mineral assemblage, presence of bytownite, 0 50 50  absence of amphibole and lack of internal fabric indicate that the rock has undergone metamorphism at a high  temperature and moderate pressure without deformation at granulite facies metamorphism. The absence of  deformation structure in the dyke is an indication that the intrusion occurred after the cessation of the regional  metamorphism but prevalent high temperature that recrystallized the rock. The whole rock composition and  some elemental ratios of the dyke indicate that the metamorphism had little or no effect on the bulk chemistry  of the rock.
date: 2023-12-07
type: Article
type: PeerReviewed
format: application/pdf
language: en
identifier: http://eprints.covenantuniversity.edu.ng/18264/1/METAMORPHIC%20EVOLUTION%20OF%20A%20METABASITE.pdf
identifier:   Oziegbe, Ehitua Julius and Ocan, O.O. and Adetunji, A. and Oziegbe, O.  (2023) METAMORPHIC EVOLUTION OF A METABASITE DYKE FROM OGBAGI AKOKO AREA, SOUTHWESTERN NIGERI.  Ife Journal of Science, 25 (3).  pp. 375-388.      
relation: 10.4314/ijs.v25i3.5