Geochemistry and mineral chemistry of pelitic gneiss of Ikare area, southwestern Nigeria
This study conducts Electron Probe Microanalysis (EPMA), X-ray Fluorescence (XRF) and Laser Ablation Inductively Coupled Plasma Spectrometry (LA-ICP-MS) analysis on the pelitic gneiss of the Basement complex of Nigeria. Phase equilibrium modeling was undertaken in the MnO–Na2O–CaO–K2O–FeO–MgO–Al2O3–...
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| Format: | Article |
| Language: | English |
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Elsevier
2021-12-01
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| Series: | Heliyon |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2405844021026463 |
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| author | Ehitua Julius Oziegbe Onesmus Ojok Ocan Gelu Costin Péter Horváth |
| author_facet | Ehitua Julius Oziegbe Onesmus Ojok Ocan Gelu Costin Péter Horváth |
| author_sort | Ehitua Julius Oziegbe |
| collection | DOAJ |
| description | This study conducts Electron Probe Microanalysis (EPMA), X-ray Fluorescence (XRF) and Laser Ablation Inductively Coupled Plasma Spectrometry (LA-ICP-MS) analysis on the pelitic gneiss of the Basement complex of Nigeria. Phase equilibrium modeling was undertaken in the MnO–Na2O–CaO–K2O–FeO–MgO–Al2O3–SiO2–H2O–TiO2–O2 (MnNCKFMASHTO) chemical system using THERMOCALC. The rock comprises of sillimanite + biotite + garnet + K-feldspar + quartz + ilmenite + plagioclase ± cordierite. Garnet has inclusions of sillimanite, biotite, and quartz. There is a very close association between biotite and sillimanite. Fibrolitic and prismatic sillimanite are both present. Fibrolitic sillimanite surrounding biotite could have possibly formed through melt-residue back reactions involving crystallization of melt. Garnet has almandine higher than 60 % and pyrope less than 33 %. Plagioclase feldspar has anorthite content between 29 and 39 %, comprising of both oligoclase and andesine. Microtextures such as cordierite corona round garnet, symplectite and kinked biotite were observed. The textural association indicates that cordierite was formed at the expense of garnet and sillimanite; garnet + sillimanite + plagioclase => cordierite + melt/fluid. Metamorphic peak conditions of 770–840 °C and 5.5–7 kbar were obtained for the mineral assemblage garnet-biotite-sillimanite-K-feldspar-quartz indicating medium-pressure granulite facies metamorphism. |
| first_indexed | 2024-04-11T21:04:40Z |
| format | Article |
| id | doaj.art-34ec883b8b5f4458beab1314f86bdb5a |
| institution | Directory Open Access Journal |
| issn | 2405-8440 |
| language | English |
| last_indexed | 2024-04-11T21:04:40Z |
| publishDate | 2021-12-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Heliyon |
| spelling | doaj.art-34ec883b8b5f4458beab1314f86bdb5a2022-12-22T04:03:22ZengElsevierHeliyon2405-84402021-12-01712e08543Geochemistry and mineral chemistry of pelitic gneiss of Ikare area, southwestern NigeriaEhitua Julius Oziegbe0Onesmus Ojok Ocan1Gelu Costin2Péter Horváth3Department of Geosciences, Faculty of Science, University of Lagos, Nigeria; Corresponding author.Department of Geological Science, College of Science, Engineering and Technology, Osun State University, NigeriaEarth, Environmental and Planetary Sciences, Rice University, Texas, USADepartment of Earth, Environmental, and Sustainability Sciences, Furman University, USAThis study conducts Electron Probe Microanalysis (EPMA), X-ray Fluorescence (XRF) and Laser Ablation Inductively Coupled Plasma Spectrometry (LA-ICP-MS) analysis on the pelitic gneiss of the Basement complex of Nigeria. Phase equilibrium modeling was undertaken in the MnO–Na2O–CaO–K2O–FeO–MgO–Al2O3–SiO2–H2O–TiO2–O2 (MnNCKFMASHTO) chemical system using THERMOCALC. The rock comprises of sillimanite + biotite + garnet + K-feldspar + quartz + ilmenite + plagioclase ± cordierite. Garnet has inclusions of sillimanite, biotite, and quartz. There is a very close association between biotite and sillimanite. Fibrolitic and prismatic sillimanite are both present. Fibrolitic sillimanite surrounding biotite could have possibly formed through melt-residue back reactions involving crystallization of melt. Garnet has almandine higher than 60 % and pyrope less than 33 %. Plagioclase feldspar has anorthite content between 29 and 39 %, comprising of both oligoclase and andesine. Microtextures such as cordierite corona round garnet, symplectite and kinked biotite were observed. The textural association indicates that cordierite was formed at the expense of garnet and sillimanite; garnet + sillimanite + plagioclase => cordierite + melt/fluid. Metamorphic peak conditions of 770–840 °C and 5.5–7 kbar were obtained for the mineral assemblage garnet-biotite-sillimanite-K-feldspar-quartz indicating medium-pressure granulite facies metamorphism.http://www.sciencedirect.com/science/article/pii/S2405844021026463THERMOCALCSillimaniteCordieriteGranuliteSymplectiteMicrotextures |
| spellingShingle | Ehitua Julius Oziegbe Onesmus Ojok Ocan Gelu Costin Péter Horváth Geochemistry and mineral chemistry of pelitic gneiss of Ikare area, southwestern Nigeria Heliyon THERMOCALC Sillimanite Cordierite Granulite Symplectite Microtextures |
| title | Geochemistry and mineral chemistry of pelitic gneiss of Ikare area, southwestern Nigeria |
| title_full | Geochemistry and mineral chemistry of pelitic gneiss of Ikare area, southwestern Nigeria |
| title_fullStr | Geochemistry and mineral chemistry of pelitic gneiss of Ikare area, southwestern Nigeria |
| title_full_unstemmed | Geochemistry and mineral chemistry of pelitic gneiss of Ikare area, southwestern Nigeria |
| title_short | Geochemistry and mineral chemistry of pelitic gneiss of Ikare area, southwestern Nigeria |
| title_sort | geochemistry and mineral chemistry of pelitic gneiss of ikare area southwestern nigeria |
| topic | THERMOCALC Sillimanite Cordierite Granulite Symplectite Microtextures |
| url | http://www.sciencedirect.com/science/article/pii/S2405844021026463 |
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