Tectonic Setting of the Syenite Around Igarra, Southwestern Nigeria: Constraints from Geochemistry

Authors

  • F. C. Ugbe
    Department of Geology, Delta State University, Abraka, Delta State, Nigeria
  • O. E. Ominigbo
    Department of Earth Sciences, Federal University of Petroleum Resources, Effurun, Delta State, Nigeria
  • A. O. Akano
    Department of Geology, Delta State University, Abraka, Delta State, Nigeria

Keywords:

Syenite, Tectonic setting, Geodynamic evolution, Pan-African orogeny, Nigerian basement complex

Abstract

Syenites are relatively rare within the Nigerian Basement Complex. As a result of their rarity, these rocks have been given less research attention over time and are consequently poorly understood. The syenitic rocks at Igarra were studied to ascertain their tectonic evolution using geochemistry. Sampling was carried out using the survey-type geological field mapping approach. A total of 10 samples of syenitic rocks were collected for laboratory analyses. Compositionally, the rocks are intermediate with regards to SiO2 content (58.02% – 60.58%), having Al2O3 and alkali (Na2O + K2O) compositional ranges of 15.34% – 15.52% and 8.99% – 9.7% respectively. The sampled rocks are similar and consistent in their trace and rare earth elements concentrations (the only exception being Zr with values ranging from 4 ppm to 79 ppm). The rocks are relatively enriched in Ba, K, TI, and Sr but depleted in Tc, Nb, U, Hf, Yb, Te and Ta. The syenites also show fairly high ratios of Rb/Nb and Rb/Sr with mean values of 488.627 and 0.171 respectively. As seen from the geochemical analyses, the syenites around Igarra are high-K calcalkaline, alkalic to alkalic-calcic. The rocks are peraluminous in character as shown by the bivariate plot of A/NK vs. A/CNK. Sedimentary protolith with continental crustal parent magma is inferred for these rocks. The similarity and consistency of the trends of major, trace and rare earth elements is indicative of cogenetic origin for the rocks. The geochemistry and discrimination plots for the rocks indicate geodynamic setting ranging from orogenic to post-orogenic. A volcanic arc geotectonic setting is interpreted for the Igarra syenites, with magma emplacement and evolution thought to have been initiated during the late stages of the Pan-African reactivation and continued into post-orogenic times.

Dimensions

M. O. Oyawoye, “The petrology of a potassic syenite and its associated biotite pyroxenite at Shaki, western Nigeria”, Contrib. to Mineral. & Petrol. 16 (1967) 115.

A. A. Makanjuola, “A review of the petrology of Nigerian syenites”, Journal of Mining and Geology 19 (1982) 1.

I. G. Egbuniwe, W. R. Fitches, M. Bentley & N. J. Snelling, “Late Pan-African syenite- granite plutons in NW Nigeria”, J. Afr. Earth Sci. 3 (1985) 427. https://doi.org/10.1016/s0899-5362(85)80085-3

A. A. Vorontsov, A. E. Izoh, V. V. Yarmolyuk, T. Y. Komaritsyna, A. V. Nikiforov, O. Y. Perfilova, S. I. Dril, N. G. Rizvanova & E. P. Dushkin, “Evolution of syenite magmas: Insight from geology, geochemistry and O-Nd isotopic characteristics of the Ordovician Saibar Intrusion, Altai-Sayan area, Russia”, Minerals 11 (2021) 473. https://doi.org/10.3390/min11050473

M. S. Kolawole, E. C. Chukwu & A. N. Aigbe, “Geochemistry and petrogenetic evolution of metasedimentary rocks in Bunu Area, part of Kabba-Lokoja-Igarra Schist Belt, SW Nigeria”, Acta Geochemica (2022). https://doi.org/10.1007/s11631-022-00545-y

J. H. Yang, J. F. Sun, M. Zhang, F. Y.Wu & S. A.Wilde, “Petrogenesis of silica- saturated and silica-undersaturated syenites in the northern North China Craton related to post- collisional and intraplate extension”, Chem. Geo. 328 (2012) 149. https://doi.org/10.1016/j.chemgeo.2011.09.011

G. N. Hanson, “The application of trace elements to the petrogenesis of igneous rocks of granitic composition”, Earth Planet. Sci. Lett. 38 (1978) 26.

E. O. Ominigbo, “Evolution of the Nigerian Basement Complex: Current Status and Suggestions for Future Research”, Journal of Mining and Geology 58 (2022) 229.

F. H. Hubbard, “Precambrian crustal development in Western Nigeria: Indications from the Iwo Region”, Geological Society Bulletin 86 (1975) 548.

H. Rollinson & V. Pease, Using Geological Data to understand Geological Processes (2nd Edition), Cambridge, Cambridge University Press (2021).

S. C. Obiora, “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 48 (2012) 13.

E. N. Ugwonah, “Trace and rare-Earth element geochemistry of the rocks of Igarra town and its environs”, COOU Journal of Physical Sciences 2 (2019) 40.

A. A. Elueze, O. Kehinde-Philips & O. A. Okunola, “Geochemical and petrogenetic trends of syenite and charnockitic rocks of Oke Iho and Osuntedo areas, southwestern Nigeria”, Journal of Mining and Geology 44 (2008) 21.

E. O. Ominigbo, E. E. Ukwang, D. P. Okumoko & U. J. Ukpai, “Petrogenesis and tectonic setting of the basement rocks around Irruan area, Bamenda Massif, SE Nigeria”, Journal of Geosciences and Geomatics 8 (2020) 35. https://doi.org/10.12691/jgg-8-1-5

A. Olajide, S. Bayode, T. Fagbemigun, A. Oyebamiji, J. Amosun & A. Omasanoye, “Evaluation of aquifer protective capacity and groundwater potential in part of Iju, Akure-North, Ondo State, Nigeria”, J. Nig. Soc. Phys. Sci. 2 (2020) 197. https://doi.org/10.46481/jnsps.2020.32

J. O. Coker, H. H. Akpan, A. O. Atilade & O. F. Ojo, “Seasonal comparison of potential groundwater aquifer in Ijebu-Ife, South-West Nigeria, using dipole-dipole array and electromagnetic methods”, J. Nig. Soc. Phys. Sci. 2 (2020) 241. https://doi.org/doi:10.46481/jnsps.2020.128

O. B. Ogbe, S. B. Olobaniyi, O. I. Ejeh, O. O. Omo-Irabor, J. Osokpor, A. Ocheli & B. Overare, “Petrological and structural investigation of the rocks around Igarra, southwestern Nigeria”, Ife Journal of Science 20 (2018) 663. https://doi.org/10.4314/ijs.v20i3.19

E. Ferre, J. Deleris, J. L. Bouchez, A. U. Lar & J. J. Peucat, “The Pan- African reactivation of Eburnean and Archaean provinces in Nigeria: Structural and isotopic data”, J. Geol. Soc. London. 153 (1996) 719.

E. Udimwen, “Paleostress configuration of Pan-African orogeny: evidence from Igarra Schist Belt, SW Nigeria”, Iranian Journal of Earth Sciences 9 (2017) 85.

M. S. Agomuo & N. Egesi, “Petrology and structural geology of Ikpeshi and its environs of Igarra Schist Belt, southwestern Nigeria”, International Journal of Science Inventions Today 5 (2016) 303.

U. A. OlaOlorun & L. O. Afolagboye, “Petrochemical characterization and geotechnical evaluation of syenite rock samples from Igarra, southwestern Nigeria”, American Journal of Engineering Research 10 (2021) 321.

M. A. A. Rahaman, “Fieldwork as a basic geologic tool”, In: Proceedings of field mapping standardization workshop, Lambert-Aikhionbare, E. & Olayinka, A. I. (Eds.), Ibadan, University of Ibadan Press (2009) 2.

S. S. Sun & W. F. McDonough, “Chemical and isotopic systematic of ocean basalts: implications for mantle composition and processes. In: Saunders, A. D. & Norry, M. J. (eds.), Magmatism in Ocean Basin”, Geological Society Special Publication 42 (1989) 313.

R. N. Thompson, “Magmatism of the British Tertiary Province”, Scott. J. Geol. 18 (1982) 49.

E. Slaby, “TAS classification – how to remove problems with postmagmatic feldspar formationin Permian volcanic rocks”, Zentraball fur Geologie und Palaontologie 15 (1994) 541.

B. N. Ekwueme, “Petrology of intermediate igneous rocks in the Oyioba-Uganga area, southern Benue Trough, Nigeria”, Journal of Mining and Geology 28 (1992) 141.

C. T. Okonkwo & I. O. Folorunso, “Petrochemistry and tectonic setting of granitic rocks in Aderan area, SW Nigeria”, Journal of Geography and Geology 5 (2013) 30.

B. R. Frost, C. G. Barnes, W. J. Collins, R. J. Arculus, D. J. Ellis & C. D. Frost, “A geochemical classification of for granitic rocks”, Journal of Petrology 42 (2001) 2033.

A. Motoki, S. E. Sichel, M. Vargas, D. P. Melo & K. E. Motoki, “Geochemical behaviour of trace elements during fractional crystallization and crustal assimilation of the felsic alkaline magmas of the state of Rio de Janeiro, Brazil”, Annals of the Brazilian Academy of Sciences 87 (2015) 1959. https://doi.org/10.1590/0001-3765201520130385

G. N. Hanson, “Rare Earth Elements in Petrogenetic Studies of Igneous Systems”, Annual Rev. Earth & Planet. Sci. 8 (1980) 371. https://doi.org/10.1146/annurev.ea.08.050180.002103

B. S. S. Jahn & R. W. Nesbitt, “REE Distribution and Petrogenesis of the Spanish Peaks Igneous Complex, Colorado”, Contrib. to Mineral. & Petrol. 70 (1979) 281.

B. W. Chapel & A. J. R. White, “I- and S-type granite in the Lachlan Belt”, Transactions in the Royal Society of Edinburgh: Earth Sciences 83 (1992) 1. https://doi.org/0.1017/S0263593300007720

P. Kamgang, E. Njonfang, A. Nono, M. G. Dedzo & F. M. Tchuoa, “Petrogenesis of silicic magma system: Geochemical evidence from Bamenda Mountains, NW Cameroon, Cameroon Volcanic Line”, J. Afr. Earth Sci. 58 (2010) 285. https://doi.org/10.1016/j.jafrearsci.2010.03.008

S. C. Obiora, “Petrology and geotectonic setting of Basement Complex rocks around Ogoja, southeastern Nigeria”, Ghana Journal of Science 46 (2006) 13.

P. D. Maniar, & P. M. Piccoli, “Tectonic discrimination of granitoids”, Geol. Soc. Amer. Bull. 101 (1989) 635.

A. Enterazi Harsini, S. A. Mazhari, S. Saadat, & J. F. Santos, “U-Pb geochronology, Sr- Nd geochemistry, petrogenesis and tectonic setting of Gandab volcanic rocks, northeastern Iran”, Geochronomateria 44 (2017) 269. https://doi.org/10.1515/geochr-2015-0061

K. C. Burke & J. F. Dewey, “Orogeny in Africa. In: Dessauragie, A. J. & Whiteman, T. F. J. (eds.)”, African Geology, University of Ibadan Press, Nigeria (1972) 583.

A. O. Oloyinde & S. B. Odeyemi, “The geochemistry, tectonic setting and origin of the massive melanocratic amphibolites in Ilesha Schist Belt, southwestern Nigeria”, Global Journal of Pure and Applied Sciences 7 (2001) 55.

F. C. Ugbe, U. P. Adiela & U. C. Ebegbare, “Major and trace element geochemistry of granites in Koji, Kogi State, Nigeria”, Research Journal of Environmental and Earth Sciences 8 (2016) 8.

V. U. Ukaegbu & B. N. Ekwueme, “Petrogenesis and geotectonic setting of the Pan-African Basement rocks in Bamenda Massif, Obudu Plateau, southeastern Nigeria: Evidence from trace element geochemistry”, Chinese Journal of Geochemistry 25 (2006) 122.

Published

2023-02-24

How to Cite

Tectonic Setting of the Syenite Around Igarra, Southwestern Nigeria: Constraints from Geochemistry. (2023). Journal of the Nigerian Society of Physical Sciences, 5(1), 999. https://doi.org/10.46481/jnsps.2023.999

Issue

Volume 5, Issue 1, February 2023

Section

Original Research
Copyright & Licensing

Copyright (c) 2023 F. C. Ugbe, O. E. Ominigbo, A. O. Akano

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite

Tectonic Setting of the Syenite Around Igarra, Southwestern Nigeria: Constraints from Geochemistry. (2023). Journal of the Nigerian Society of Physical Sciences, 5(1), 999. https://doi.org/10.46481/jnsps.2023.999

Similar Articles

21-30 of 101

You may also start an advanced similarity search for this article.