Deciphering Paleoclimate and Provenance Signals in Niger Delta Clay Deposits Using Major Oxide Geochemistry and Weathering Indices

Abstract

This study investigates the major oxide geochemistry of clay deposits within the 
Niger Delta to evaluate their provenance, weathering characteristics, depositional 
environment, and industrial suitability through integrated geochemical and 
statistical approaches. Twelve representative clay samples were collected from 
selected locations across the study area and analyzed for major oxide composition 
using Inductively Coupled Plasma–Optical Emission Spectrometry (ICP–OES). The 
analyzed oxides include SiO₂, Al₂O₃, Fe₂O₃, MnO, MgO, CaO, Na₂O, K₂O, TiO₂, and 
P₂O₅, together with Loss on Ignition (LOI). Geochemical results indicate that SiO₂ 
is the dominant oxide, with concentrations ranging from 42.21% to 91.91% and an 
average value of 71.06%, suggesting quartz-rich, compositionally mature, and highly 
weathered sediments. Al₂O₃ and Fe₂O₃ recorded average concentrations of 13.58% 
and 3.44%, respectively, reflecting appreciable contributions from clay minerals and 
ferruginous components. The generally low concentrations of CaO and MgO indicate 
minimal marine influence and support deposition within predominantly fluvial to 
deltaic settings. Statistical analyses reveal a strong negative correlation between 
SiO₂ and Al₂O₃, indicating silica enrichment associated with sediment recycling and 
prolonged chemical weathering under tropical climatic conditions. In contrast, 
positive correlations between Fe₂O₃ and Al₂O₃ suggest a common lithogenic origin 
and similar geochemical behavior during sedimentation. Graphical and statistical 
interpretations further indicate felsic continental provenance, advanced 
weathering intensity, and significant sediment maturity. The study concludes that 
the clay deposits were principally derived from intensely weathered continental 
source rocks and, although limited in high-grade industrial applications due to 
elevated silty content, remain suitable for the production of building blocks, 
pottery, and thermal insulation materials.