Author(s)

Olusegun G. Olisa^1*, Olugbenga A. Okunlola², Ayotunde A. Omitogun²

¹Department of Geology, PAULESI, University of Ibadan, Ibadan, Nigeria.
²Department of Geology, University of Ibadan, Ibadan, Nigeria.

The study was carried out to delineate the geochemistry of unstudied meta-sedimentary rocks in the Igangan sheet 240 NW. Geological field mapping was undertaken to delineate the different metasedimentary rocks; three different metasedimentary rocks were observed and 17 samples were analyzed using ICP-AES/MS to obtain elemental concentrations. Geochemical analytical results revealed average concentration (%) of 74.5, 12.66, 1.99, 4.23, and 3.59 for SiO₂, Al₂O₃, Fe₂O₃, Na₂O and K₂O respectively. Trace elemental average concentrations (ppm) for selected trace elements in the metasediments are as: U (0.4 - 4.8 ppm, 2.39), Th (0.9 - 25.60 ppm, 10.38), Ni (0.1 - 17.70 ppm, 7.40), Sr (37 - 124 ppm, 81.75), Ba (55 - 1228 ppm, 620.31), Sn (1.4 - 4.8), Be (1 - 11 ppm, 3.31), Li (2.6 - 48.50 ppm, 23.28), Rb (32 - 376.3 ppm, 140.16), Ta (0.5 - 65.20 ppm, 12.48), Nb (7.76 - 47.5 ppm, 23.82) and Cs (0.8 - 33.30 ppm, 8.33). REE patterns of all samples are parallel to sub-parallel, LREE-enriched, with weak to distinct negative Eu anomalies and weakly fractionated HREE segments. Source rocks of the metsediments underwent low to moderate chemical weathering and metasediments are derivatives of felsic igneous sources.

Phyllite, Sediment Recycling, Depositional Regimes

Olisa, O. , Okunlola, O. and Omitogun, A. (2018) Petrochemistry and Petrogenetic Features of Metasedimentary Rocks of Igangan Area, Southwestern Nigeria. Journal of Geoscience and Environment Protection, 6, 49-66. doi: 10.4236/gep.2018.64004.