Petrogenesis and Tectonic Setting of the Basement Rocks around Irruan Area, Bamenda Massif, SE Nigeria

Ominigbo O. E.^1, , Ukwang E. E.¹, Okumoko J. P.² and Ukpai U. J.¹

¹Department of Geology, Faculty of Physical Sciences, University of Calabar, Calabar, Nigeria

²Department of Earth Sciences, College of Sciences, Federal University of Petroleum Resources, Effurun, Nigeria

Cite this paper:
Ominigbo O. E., Ukwang E. E., Okumoko J. P. and Ukpai U. J.. Petrogenesis and Tectonic Setting of the Basement Rocks around Irruan Area, Bamenda Massif, SE Nigeria. Journal of Geosciences and Geomatics. 2020; 8(1):35-44. doi: 10.12691/jgg-8-1-5

Abstract

The basement rocks around Irruan in southern Obudu Plateau, southeastern Nigeria were studied using field mapping and geochemical data. Both igneous (granodiorite and biotite granite) and metamorphic rocks (granite gneiss, banded gneiss and migmatite gneiss) were mapped in the area. The rocks are generally quartzofeldspathic and range from alkali-calcic to calc-alkali. Fairly strong negative correlation exists between Al₂O₃ and Na₂O with SiO₂ as well as between Al₂O₃ and Fe₂O₃. The magma source for the Irruan granitoids is continental as indicated by the high SiO₂ content (≥70.11 wt.% except the biotite granite that records 61.10 wt.% of SiO₂) and discriminant plots for the area. A sedimentary protholith has been interpreted for the gneissic rocks. Magmatism in the area commenced during the later stages of the Pan-African orogeny and continued much into the post-orogenic period, leaving behind, imprints of syn-collosional and post-orgenic tectonic settings.

Keywords:
petrogenesis tectonic setting magmatism syn-collisional Obudu Plateau Bamenda massif

This work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

References:

[1]	Obiora, S. C. (2012). Chemical Characterization and Tectonic Evolution of Hornblende-Biotite Granitoids from the Precambrian Basement Complex around Ityowanye and Katsina-Ala, southeastern Nigeria. Journal of Mining and Geology, vol. 48 (1), pp. 13-29.
[2]	Obiora, S. C. (2006). Petrology and geotectonic setting of Basement Complex rocks around Ogoja, south-eastern Nigeria. Ghana Journal of Science, vol. 46, pp. 13-25.
[3]	Ekwueme, B. N. (1990). Rb-Sr Ages and Petrologic Features of Precambrian Rocks from the Oban Massif, Southeastern Nigeria. Precambrian Research, vol. 47, pp. 271-286.
[4]	Ukwang, E. E. and Ekwueme, B. N. (2009). Trace element geochemistry and tectonic setting characterization of granulite facies rocks from southwest Obudu Plateau, southeastern Nigeria. Chinese Journal of Geochemistry, vol. 28(3), pp. 248-257.
[5]	Ephraim, B. E., Ekwueme, B. N. and Adamu, I. C. (2006): Preliminary Report on the Geology of Northeast Obudu, Bamenda Massif, Southeastern Nigeria. International Journal of Natural and Applied Sciences, vol. 1 (1), pp. 84-89.
[6]	Ukwang, E. E., Ekwueme, B. N. and Horsley, R. J. (2003). Petrology and Granulite Facies Rocks in Ukwortung Area of Obudu Plateau, South Eastern Nigeria. Global Journal of Geological Sciences, vol. 1 (2), pp. 159-168.
[7]	Ominigbo, O. E. (2020). Petrology and structural attributes of the Basement Rocks around Irruan, Obudu Plateau, southeastern Nigeria. Unpublished M.Sc. thesis submitted to the Department of Geology, University of Calabar, Nigeria.
[8]	Ukwang, E. E., Ekwueme, B. N. and Kroner, A. (2012). Single Zircon Evaporation Ages: Evidence for the Mesoproterozoic Crust in Southeastern Nigerian Basement Complex. Chinese Journal of Geochemistry, vol. 31, pp. 048-054.
[9]	Ekwueme, B. N. and Kroner, A. (1998). Single Zircon Evaporation Ages from the Oban Massif, southeastern Nigeria. Journal of African Earth Sciences, vol. 26 (2), pp. 195-205.
[10]	Kouankap-Nono, G. D., Wotchoko, P., Magha, A., Ganno, S., Njoya, N., Afahnwie Ngambu, A., Nzenti, J. P. and Kamgang Kabeyene, V. (2018). Contrasting Ba-Sr Granitoids from Bamenda Area, NW Cameroon: Sources, Characteristics and Implications for the Evolution of the Pan African Fold Belt. Journal of Geosciences and Geomatics, vol. 6 (2), pp. 65-76.
[11]	Bate-Tibang, E. E. B., Suh, C. E., Cottle, J., Ateh, K. I., Tiabou, A. F., Nche, L. A., Che, V. B. and Vishiti, A. (2017). Petrology and geochronology of felsic volcanics in the Sabga area (Bamenda Highlands): implications for age variation along the Cameroon Volcanic Line. Journal of Geoscioences, vol. 62, pp. 231-246.
[12]	Obioha, Y. E and Ekwueme, B. N. (2011). Petrology and chemical composition of gneisses of northwest Obudu Plateau, southeastern Nigeria. Global Journal of Pure and Applied Sciences, vol. 17 (2), pp. 215-226.
[13]	Beka, F. and Ukaegbu, V. (2009). Petrology and major element geochemistry of high-K peraluminous granites in southeast Obudu Plateau, southeastern Nigeria. Journal of Mining and Geology, vol. 44 (2).
[14]	Rahaman, M. A. (1989). Review of the Basement Geology of South Western Nigeria. In Kogbe, C. A. Geology of Nigeria (2nd Edition), Rock View, pp. 39-56, Jos.
[15]	Rahaman, M. A. (1988). Recent Advances in the Study of the Basement Complex of Nigeria. In Precambrian Geology of Nigeria, Geological Survey of Nigeria, Kaduna South, pp. 11-43.
[16]	Odeyemi, I. B. (1981). A Review of the Orogenic Events in the Precambrian Basement of Nigeria, West Africa. Geologische Rundschau, vol. 70 (3), pp. 897-909.
[17]	Rahaman, M. A. O. (2009). Field Work as a Basic Geological Tool. InProceedings of Field Mapping Standardization Workshop, Lambert-AikhionbareandOlayinka, A. I. (Eds.), Ibadan University Press, Ibadan. P.2.
[18]	Tsuchiya, N., Shibata, T., Koide, Y., Owada, M., Takazawa, E., Goto, Y., Choi, J. H., Terada, S. and Hariya, Y. (1989). Major Element Analysis of Rock Samples by X-ray Fluorescence Spectrometry, using Scandium Anode Tube. Journal of Faculty of Science, Hokkaido University, vol. 22 (3), pp. 489-502.
[19]	Okonkwo, C. T. and Folorunso, I. O. (2013): Petrochemistry and geotectonic setting of granitic rocks in Aderan area, SW Nigeria. Journal of Geography and Geology, vol. 5(1), pp. 30-44.
[20]	Frost, B. R., Barnes, C. G., Collins, W. J., Arculus, R. J., Ellis, D. J and Frost, C. D. (2001). A Geochemical Classification for Granitic Rocks. Journal of Petrology, 42 (11), pp. 2033-2048.
[21]	Obasi, R. A. (2016). Geochemistry, S-Type Classification and Petrography of Granites from Idanre, Ondo State, South West Nigeria. International Journal of Scientific and Engineering Research, vol. 7 (12), pp. 859-879.
[22]	Lopez de Luchi, M. G., Cerredo, M. E., Siegesmund, S., Steenken, A. and Wemmer, K. (2003). Provenance and Tectonic Setting of the Protoliths of the Metamorphic Complexes of Sierra de San Luis. Revista de la Geologica Argentina, vol. 58 (4), pp. 525-540.
[23]	Pearce, J. A., Harris, N. B. W. and Tindle, A. G. (1984). Trace Element Discrimination Diagrams for the Tectonic Interpretation of Granitic Rocks. Journal of Petrology, vol. 25 (4), pp. 956-983.
[24]	Kanouo, N. S., Yongue, R. F., Ghogomu, T. R., Njonfang, E., Yomeun, S. B. and Basau, E. A. A. (2017). Petro-geochemistry, Genesis and Economic Aspects of Mafic Volcanic Rocks in the West and Southern part of the Mamfe Basin (SW Camerron, Central Africa). Journal of Geology &Geophysics, vol. 6(4), 298.
[25]	Maniar, P. D. and Piccoli, P. M. (1989). Tectonic Discrimination of Granitoids. Geological Society of America Bulletin, 101, pp. 635-643.
[26]	Odewumi, S. C. and Olarewaju, V. O. (2013). Petrogenesis and Geotectonic Settings of the Granitic Rocks of Idofin-Osi-Eruku Area, Southwestern Nigeria using Trace Element and Rare Earth Element Geochemistry. Geology & Geosciences, vol. 2(1).
[27]	Enterazi Harsini, A., Aamazheri, S. A., Saadat, A. and Santos, J. (2017): U-Pb Geochronology, Sr-Nd Geochemistry, Petrogenesis and Tectonic Setting of Gandab Volcanic Rocks, Northeastern Iran. Geochronomateria, vol. 44, pp. 269-286.
[28]	Usman, M. A. and Ibrahim, A. A. (2017). Petrography and Geochemistry of Rocks of Northern Part of Wonaka Schist Belt, Northwestern Nigeria. Nigerian Journal of Basic and Applied Sciences, vol. 25 (2), pp. 87-99.
[29]	Katongo, C., Koller, F., Kloetzli, U., Koeberl, C., Tembo, F. and Waele, B. D. (2004). Petrography, Geochemistry and Geochronology of Granitoid Rocks in the Neoproterozoic-Paleozoic Lufilian-Zambezi Belt, Zambia: Implications for Tectonic Setting and Regional Correlation. Journal of African Earth Sciences. Vol. 40, pp. 219-244.
[30]	Ukaegbu, V. U. and Ekwueme, B. N. (2006). Petrogenesis and Geotectonic of the Pan- African Basement Rocks in Bamenda Massif, Obudu Plateau, southeastern Nigeria: Evidence from Trace Element Geochemistry. Chinese Journal of Geochemistry, vol. 25 (2), pp. 122-131.
[31]	Ibe, C. U. and Obiora, C. S. (2019). Geochemical characterization of Granitoids in Katchuan Irruan area: further evidence for peraluminous and shoshonitic compositions and and post-collisional setting of granitic rocks in the Precambrian Basement Complex of Nigeria. Acta Geochemical, vol. 38 (5), pp. 734-752.