The geochemical composition of sediment as a proxy of provenance and weathering intensity: a case study of Southwest Nigeria’s Coastal Creeks

Abstract

The study of the geochemical composition of sediments was undertaken to evaluate the degree of weathering and appraise the relative proportion of mafic and felsic rock materials being transported from source to sink. Thirty-three surface sediment samples collected from the creeks were used for particle size and chemical analyses. An inductively coupled plasma-Mass Spectrometer was used to determine the elemental composition of the sediments. The clay dominated Yewa and western Badagry creeks gave evidence of higher average concentrations of Ni, Sr, Y, Nb, Sc, Co, V, and Th than the eastern end of segment of Badagry Creek. The data generated from elemental ratios such as Al 2 O 3 /TiO 2 , TiO 2 /Zr and binary plots of Th/Sc-Cr/Sc, Th-Sc, Y/Ni-Cr/V, TiO 2-Zr and ICV-CIA (index of compositional variability against chemical index of alteration) showed that source sediments are composed of upper and lower crustal compositions. Also, the creeks were marked by their variation in terms of the proportion of felsic and mafic components. For instance, Yewa and western Badagry creeks are more enriched in mafic constituents, whereas the enrichment of felsic materials is significant at the eastern end of Badagry Creek. Inferring from the chemical index of alteration and plagioclase index of alteration (PIA), the Yewa and western Badagry creeks have been moderately to intensely weathered and incipient weathering was identified in the eastern end of Badagry Creek.

Chemostratigraphic Approach to the Study of Resources’ Deposit in the Upper Silesian Coal Basin (Poland)

“…Trace element composition can potentially provide information regarding the provenance of terrigenous sediments and source-area rock compositions [26,46,[49][50][51][52][53][54][55][56].…”

“…The ratios of Al 2 O 3 /TiO 2 and TiO 2 /Zr as well as the abundance of trace elements, such as Zr, La, Sc, Th, and their elemental ratios (Th/Sc and La/Th), are commonly used in provenance studies (e.g., [18,26,46,[49][50][51][52][53][54][55][56][57][58][59]).…”

“…The Al 2 O 3 /TiO 2 ratio is used to identify source materials, since the Al 2 O 3 /TiO 2 values in sedimentary rocks are basically preserved from their parent rocks and do not change significantly during chemical weathering, transport, sedimentation, and diagenesis [18,45,47,[50][51][52][53][54][55]. Al 2 O 3 /TiO 2 ratios range from 3 to 8, 8-21, and 21-70 for mafic, intermediate, and felsic sources, respectively [52].…”

“…Sc and Th are transferred quantitatively from source to sediment. Thus, the Th/Sc ratio can be used to distinguish between felsic and mafic sources [46,49,52,[54][55][56][57][58][59]. Th/Sc ratios of ≥1.0 are typical of continental crust enriched in incompatible elements, ≥0.6-1.0 indicates an andesitic composition, and <0.6 typifies a mafic signature.…”

Geochemical elements as provenance and paleoenvironmental indicators in siliciclastic sediments of Neogene Gwandu formation exposed in Birnin Kebbi Area, Northwestern Nigeria

“…Elsewhere in Nigeria, several researches have been undertaken on geochemistry of Cretaceous, Tertiary and Quaternary sediments with emphasis on various provenance indicator elements (Amajor, 1987;Ehinola and Abimbola, 2002;Madukwe and Bassey, 2015;Phillips et al, 2017a;2017b;Madukwe, 2019;Amiewalan et al, 2020;Overare et al, 2020;Ojo et al, 2021).…”