Textural and geochemical characteristics of the Yikpata river channel sands, Nigeria

Abstract

The Yikpata river is one of the major rivers that empty into the River Niger, Nigeria. River Niger cuts across the Bida Basin thereby contributing to the alluvium deposits found within the Bida Basin. The properties and compositions Yikpata river channel sediments input in the River Niger where alluvium deposits are found is yet to be documented. Furthermore, the geology of where the studied river is located is sparse. Therefore, the textural, petrological, and geochemical analyses were used to examine the Yikpata river channel sediments for their compositions and characteristics in other to infer their provenance, tectonic settings and chemical weathering intensity as well as give information about sediments that are been transported as recent alluvium along River Niger in the Bida Basin. This study likewise lays some foundations for the comprehensive assessment of watershed environmental quality. This study revealed that the Yikpata river channel sediments are moderately well to poorly sorted sediments and were classified as sub-arkose based on log Na2O/K2O vs SiO2/Al2O3. Low CIA, PIA, ICV, Rb/Sr values, and ternary plot of A-CN-K demonstrate that the river sands were derived from low to moderately weathered source rocks and the major-element-based discrimination diagrams revealed that sediments were from a rift tectonic setting (passive margin). Additionally, the river sediments are derived from weathered sedimentary rocks that are of the felsic source, based on the major element discriminates functions, TiO2 vs Zr, Al2O3/TiO2, La/Sc, La/Co, Th/Sc, Cr/Th and LREE/HREE. The pollution status of the river from the sediments revealed that the river is currently not polluted and the sediment is not toxic.