Major and Trace Element Geochemistry of Granites in Koji, Kogi State, Nigeria

F. C. Ugbe ； Uche-Peters Adiela ； U. C. Ebegbare

《Research Journal of Environmental and Earth Sciences》 8卷1期 (2016/02) Pp. 8-12

https://doi.org/10.19026/rjees.8.2697

並列摘要

Major and trace elements geochemistry of Koji granites were determined to deduce the petrogenesis of the rocks. Six granite rock samples were collected and analyzed for their major and trace elements using the Inductively Coupled Plasma Mass Spectrometer Methods. From the major element geochemistry, SiO_2 ranges from 69.34%-72.97% and hence suggests a felsic granite. The strong correlation between SiO_2 and CaO, MgO, Na_2O and Fe_2O_3, suggest that the primary mineral assemblage may have undergone significant changes during fractionation. The high K2O content suggests the abundance of K-feldspar in the rock. From the trace element geochemistry, the High Field Strength Elements (HFSE) and the Large Ion Lithophile Elements (LILE) is consistent with values of the average granite and crust. The depletion of Sr suggests plagioclase fractionation. The plot of A/CNK against SiO_2 indicates a S-type granitoid and on the basis of alumina saturation, it suggests a peraluminous granite. Based on the A/CNK against SiO_2 plot and alumina saturation plot the geotectonic setting indicate volcanic arc syn-collisional granites.

並列關鍵字

Fractionation ； peraluminous ； syn-collisional granites ； volcanic arc