Browsing by Author "Bamigboye, Olufemi Sijuade"

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    Geochemistry of Aliphatic Hydrocarbon Compounds in Core Sediments from Sadong River, Malaysia
    (2023) Omorinoye Ajoke Omorinoye; Assim, Z.B; Jusoh I.B.; Bamigboye, Olufemi Sijuade; Alebiosu Mercy Titilayo
    Sadong River is a major river catchment in Sarawak, Malaysia. Sediments are useful tools in understanding the environmental processes and are final sinks of hydrocarbons in rivers. Hydrocarbon biomarkers are organic compounds found in the environment with structures suggesting an unambiguous connection with known contemporary natural products. These specific indicator compounds which are found in extracts of geological and environmental sample such as sediment can be utilized for genetic source correlations. Hydrocarbons derived from biogenic sources appear with low concentrations in river sediments, while high level of concentration in hydrocarbon compounds are attributed to be of anthropogenic source which often lead to petroleum pollution. Several indices were used to distinguish the origin of n-alkanes in the river such as Low Molecular Weight to High Molecular weight (LMW/HMW), Carbon Preference Index (CPI) and Average Chain Length (ACL). Assessment of n-alkanes in the core sediments showed the hydrocarbons originated from terrestrial sources and anthropogenic sources.
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    Petrography, Geochemistry and Petrogenesis of grey Gneisses of part of Oke-Ode Area, South-Western Nigeria
    (2022) Adedoyin, Adeonipekun Dele; Alebiosu, Mercy Titilayo; Bamigboye, Olufemi Sijuade; Olobaniyi S.B.; Omorinoye, Omolayo Ajoke; Iheme, Kenneth Obinna
    Oke-Ode area, northeast of Ilorin, is part of the Precambrian Basement Complex of southwestern Nigeria. There are no published data on the gneisses, which are well exposed, unlike the adjacent terrains. The area was mapped in order to determine the petrographic, geochemical and petrogenetic attributes of the grey gneisses. The acquired sets of field, mineralogical, and geochemical data indicated that the medium-to coarse-grained gneisses are of igneous origin, and have witnessed multiple tectono-thermal readjustments. Occurrence of xenoliths in the rocks points to magmatic origin. The range of anorthite molecular contents of the plagioclase (An26-34) suggests an andesine to oligoclase composition, indicating derivation from granodioritic to tonalitic progenitors. Petrographic studies showed that the rocks witnessed complex interplay between metamorphism, deformation, and migmatization, which culminated in grain-boundary migration under a relatively stable, low-strain, hightemperature conditions involving mechanical rotation, during grain-scale dynamic recrystallization. Geochemically, plots of Ni vs Zr/TiO₂ and K₂O/Al₂O₃ vs Na₂O₃/Al₂O₃ also constrained the the gneisses to the igneous field while the TiO2 - K2O - P₂O₅ ternary plot further indicated a continental tectonic setting prior to the widespread Pan African magmatism. The rocks are essentially peraluminous calc-alkaline rocks, which are moderately saturated with respect to silica. They are products of fractional crystallization of a basaltic magma in a continental setting but later reworked during the Pan African time. The grey gneises have similar geo-chemical characteristics with some gneisses from other parts of the Basement Complex of Nigeria, but at distinct variance with others.