Major, Trace and Rare Earth Elements Geochemistry of Isan Clay Southwestern Nigeria: Implications for Provenance

Abstract

Isan clay occurs within the Precambrian Basement rocks in the southwestern Sector of the Nigerian Basement Complex. This present study focuses on the determination of the provenance of Isan clay using major, trace and rare earth elements geochemistry. Representative clay samples were collected at different horizons and subjected to Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) analysis. On the TiO vs Al O diagram, Isan clays plot in 2 2 3 the granite/rhyolite field. This indicates that the provenance of Isan clay is predominantly from felsic rocks. The provenance of Isan clay could thus be attributed to the granitic rocks from Isan area. On the La versus Th plot, Isan clays data fall below the range of UC with all the samples having a significant felsic component. This suggests that Isan clays have a uniform provenance of felsic component and exhibited high ratios of La/Co, Th/Co, La/Cr, Th/Cr and Ba/Co which indicate that the clays were derived mainly from felsic rocks. The clays have fractionated REE patterns, the LREE are enriched and the HREE patterns are almost depleted. The (La/Yb) ratio of Isan clay ranges N from 4.96 to 15.96 and (Gd/Yb) ratio ranges from 1.20 to 1.68 with a negative Eu anomaly of 0.50 to 0.67. These N characteristics attest that the provenance of Isan clay was felsic and the negative Eu anomaly is regarded as evidence of a differentiated source, similar to granite.

Publication Info:

Author: Odewumi, S.C. and Adekeye, J.I.D.

Volume: 56

Issue: March

Published By: Journal of Mining and Geology, 2024-03-01