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The Dahomey Basin, located in southwestern Nigeria, is an energy-rich frontier basin with sedimentary successions consisting of both (onshore) terrestrial and (offshore) marine deposits. Since the discovery of several bitumen seeps, tar sands, and oil and gas shows offshore the basin and the successful production of the Aje Field, the basin has gained immense interest from academia and industry. Nevertheless, surface and subsurface research focusing on paleoclimatic conditions, primary productivity, anoxic conditions, paleowater depth, and hydrodynamic influence in the Dahomey Basin is less documented. To reconstruct paleoenvironmental conditions, subsurface data from the Araromi-Obu (A1) and Idiobiolayo (A15) cores were used. The average chemical index of alteration (CIA) values ranging from 63.01 to 94.88 reflect varying degrees of weathering intensity in the sediment source area of the Cretaceous Araromi Formation. These values show a transition from relatively low to considerably high degrees of weathering in the source region of the Araromi Formation. The analysis of CIA values and Ga/Rb, Sr/Cu, Sr/Ba, Ca/Al, and 100*Mg/Al ratios suggests that the Araromi Formation was deposited in a brackish to marine environment. Furthermore, chemical alteration-sensitive geochemical indicators revealed prevailing warm, humid tropical climates during the late Cretaceous period, with likely minor arid intervals. In addition, the geochemical markers used (Ba/Al, U/Th, Ni/Co, authigenic uranium (Uau), P/Ti, and [(Fe 2 O 3 + CaO + MgO)/(SiO 2 + Al 2 O 3)] indicate poor paleoproductivity for the Araromi Formation deposited in an oxygen-rich marginal to shallow marine environment. The upper Cretaceous period was characterised by fluctuating hydrodynamic circulation, with a weak hydrodynamic regime in core A1 and transitioning to strong hydrodynamic conditions in core A15. The inferred paleowater depth corresponds to the salinity measurements, with the A1 core displaying elevated salinity, indicating a greater depth compared to the A15 core, which was deposited in a shallower environment and displays lower salinity. • Paleoredox-sensitive geochemical indicators reveal dominantly weak reducing conditions. • New insights on paleowater and salinity levels in the Dahomey Basin. • Major oxides and trace element proxies revealed brackish to marine environment. • Prevailing warm, humid tropical climates with intermittent arid climates during the Late Cretaceous in the Dahomey embayment. • In the Dahomey Basin, climatic fluctuations impacted the salinity levels. [ABSTRACT FROM AUTHOR]

Lateritic soils are prevalent in the tropical regions, and they are used for various construction purposes including landfill liner applications. However, their contaminant attenuation potentials through sorption and the influence of parent rocks on this property are poorly understood. This study investigates lateritic soils from southwestern Nigeria as barrier to leachate migration in engineered landfills and related waste containment facilities. The lateritic soils were investigated through X-ray diffraction (XRD), geochemical analysis and batch equilibrium sorption test to evaluate the competitive sorption of Mn, Cd, Pb, Cu and Cr which are common in landfill leachates. The XRD analysis shows that the kaolinite and dickite are the dominant clay minerals present in the lateritic soils, implying low desiccation cracking and low shrink-swell behaviour. The geochemical analysis indicate that the lateritic soils are silico-alumino-feruginuous with average major oxide composition of SiO 2, Al 2 O 3 and Fe 2 O 3 of 50.86 wt%, 29.83 wt% and 14.29 wt%), respectively. Additional oxides with lower abundance include TiO 2 (1.55 wt%), Na 2 O (0.01 wt%), MgO (0.36 wt%), CaO (0.15 wt%) and K 2 O (1.52 wt%). The lateritic soils contain trace amount of heavy metals with average concentrations of Cd (0.039 ppm), Pb (0.548 ppm), Cr (0.189 ppm), Cu (0.964 ppm), Mn (0.145 ppm). Furthermore, the low abundance of sodium oxide in the lateritic soils indicates that the soil particles are not susceptible to dispersion while the presence of considerable amount of iron and manganese oxides signify its good heavy metal retention. The batch equilibrium sorption analysis shows that the lateritic soils derived from granite-gneiss and charnockite exhibit better sorption potential than those derived from schist and quartzite. This high sorption capacity is intricately related to the presence of goethite in the soils. The sorption of these trace metals onto the lateritic soils follows Langmuir type isotherm and these isotherms deviate from the corresponding desorption isotherms to different degrees indicating various extents of hysteresis. The sorption hysteresis indices for these trace metals range from 0.63 to 0.99 and imply that the trace metals may re-leached to the surrounding soils and groundwater. Thus, it is recommended that landfill liners utilizing these lateritic soils are design as a composite containment facility by integrating compacted soil liners, leachate collection systems and monitoring networks to ensure effective environmental protection. • Kaolinite and dickite dominate the lateritic soils. • The lateritic soils exhibited a pronounced tendency for the sorption of Pb and Cd. • Soils derived from granite-gneiss and charnockite showed better sorption than schist and quartzite. • Sorption isotherms exhibit varying degrees of deviation from desorption isotherms. • Hysteresis index indicates significant desorption potential. [ABSTRACT FROM AUTHOR]

[Display omitted] • Identification and collection of raw magnetic sand from site. • Characterization of raw magnetic sand. • Synthesis of mesoporous iron oxide from the raw magnetic sand. • Characterization of synthesized mesoporous iron oxide. This paper presents the synthesis of iron oxide from natural magnetic sand that was obtained from Michika, Adamawa State, Nigeria. Characterization of the raw magnetic sand and the synthesized iron oxide was performed to investigate the effect of the synthesis method on functional groups, morphology, composition, crystallinity, acidity and surface area/pore distribution using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy – energy dispersive X-ray (SEM – EDX), X-ray fluorescence (XRF), X-ray diffraction (XRD), BET and pyridine FTIR, respectively. The XRF analysis of the two samples revealed a significant variation in oxide composition. The raw magnetic sand had an iron oxide content of 64.69 wt%, which increased to 85.20 wt% after synthesis. Furthermore, the SEM-EDX analysis indicated a decrease in average particle size from 114.6 and 36.8 µm for the respective samples. The XRD patterns revealed that the crystallinity increased after synthesis. FTIR showed the associations of functional groups present in the sample. The wavebands in the range 550 – 630 cm−1, which correspond to the Fe – O bond, improved clearly in the synthesized iron oxide sample, particularly at 582 cm−1. The pyridine FTIR depicts that the overall acidic site is higher in the synthesized sample. The N 2 adsorption–desorption procedure shows an increased BET surface area from 9.394 m2/g (raw) to 24.851 m2/g (synthesized). Overall, the results showed that the synthesized mesoporous iron oxide exhibits properties similar to materials that have a high potential for application as catalysts in chemical processes. [ABSTRACT FROM AUTHOR]

The operational effectiveness of a fluid catalytic cracking unit largely depends on its catalyst, which is a mixture of zeolite, binder, matrix and filler. The filler plays an active role as it provides the catalyst with physical strength and integrity and also presents a heat exchange platform where more imperative and costly zeolite component can be incorporated. In Nigeria, foreign kaolin clay is used as fillers because it contains lesser impurities when compared to the one indigenous to the country. In contrast, Nigeria bentonite clay have unique properties that can be processed and used as an alternative. This paper evaluates the suitability of kaolin and sodium bentonite from southern Nigeria as fillers in the Fluid Catalytic Cracking Unit. Initial characterisation with the aid of an XRF analysis confirmed the presence of iron oxide impurity on both the local and foreign crude clay (Bavaria, Germany). Wet beneficiation processes were carried out on all clay samples with different reaction times, temperatures and amounts of reagents to reduce impurities. Reaction time at 8 h proved more effective as 77% of iron oxide were removed from both the local and foreign clays. The product properties of the beneficiated samples also revealed iron oxide impurities that reduce impurities from 5.62% to 1.41% for kaolin clay and from 9.84% to 2.77% for bentonite clay. Samples of crude oil and products were tested to determine their physical properties using an Emmetteller Brunauer, a scanning electron microscope, a viscometer, and a pH meter to reveal the impact of the benefits on compliance with API standards. Aside from the increase or decrease of particulate or grain size, the structural modifications reflect the impact of mineral clay in retaining exchangeable cations (nutrients). [ABSTRACT FROM AUTHOR]

The high-K calc-alkaline granitoids in the northern part of the Mandara Hills are part of the well-exposed post-collisional plutons in northeastern Nigeria. The calc-alkaline rock association consists of quartz monzodiorite, hornblende biotite granite, biotite granites and aplite which intruded the older basement consisting mainly of low-lying migmatitic gneisses and amphibolites during the Neoproterozoic Pan-African Orogeny. Petrological and geochemical studies have revealed the presence of hornblende, iron oxide, and metaluminous to slightly peraluminous characteristics in the granitoids which is typical of I-type granite. The granitoids are also depleted in some high field strength elements (e.g. Nb and Ta) as well as Ti. Plots of Mg# versus SiO2 indicate that the granite was derived from partial melting of crustal sources. Lithospheric delamination at the waning stage of the Pan-African Orogeny possibly triggered upwelling of hot mafic magma from the mantle which underplated the lower crust. This, in turn, caused partial melting and magma generation at the lower to middle-crustal level. However, the peculiar geochemical characteristics of the quartz monzodiorite especially the enrichment in compatible elements such as MgO, Cr, and Ni, as well as LILE element (e.g. K, Ce, Cs, Ba, and Sr), signify that the rock formed from an enriched upper mantle source. The emplacement of high-K granites in the Madara Hill, therefore, marked an important episode of crustal reworking during the Neoproterozoic. However, further isotopic work is needed to confirm this model. [ABSTRACT FROM AUTHOR]

Introduction: Watermelon is one of the commonly eaten fruit in most homes in Nigeria and has been used in the management of diabetes mellitus traditionally. This study was carried out to explore the antidiabetic potential of watermelon (Citrullus lanatus) juice in alloxan-induced diabetic rats. Methods: Watermelon juice was used for the determination of in vitro parameters such as 1,1-diphenyl-2-picryl-hydrazil (DPPH), nitric oxide and ferric reducing antioxidant potential (FRAP) as well as phytochemicals such as total phenol, total flavonoids. In vitro, α-glucosidase and α-amylase inhibitory activities were also accessed using standard procedures. Diabetes was induced in the rats by a single intraperitoneal (I.P) injection of freshly prepared alloxan (150 mg/kg body weight). The animals were randomly grouped into five groups of normal control, untreated diabetic control, diabetic rats administered 200 mg/kg body weight of metformin, diabetic rats administered 500 mg/kg body weight of watermelon (Citrullus lanatus) juice and diabetic rats administered 1000 mg/kg body weight of watermelon juice. The rats were sacrificed on the 14th day of the experiment and various in vivo biochemical parameters were also evaluated in the serum and tissue homogenates of diabetic rats. Results: The watermelon juice exhibits anti-oxidant properties and inhibitory activities against α-glucosidase and α-amylase in a dose-dependent manner. Added to this, the administration of different doses of the watermelon juice significantly (p < 0.05) reduced the fasting blood glucose level, serum lipid profile, glucose-6-phosphatase, lipid peroxidation and anti-inflammatory activities in alloxan-induced diabetic rats. There was a significant (p < 0.05) increase in antioxidant enzyme activities, hexokinase activity as well as glucose transporters (GLUT 2 and GLUT 4) levels in diabetic rats administered different doses of Citrullus lanatus. Conclusion: Taken together, this study demonstrates that watermelon (Citrullus lanatus) juice exhibits its antidiabetic potential in experimental diabetic animal model via multiple pathways involving modulation of glucose transporters, anti-inflammatory activities as well as antioxidant defense system and inhibition of α-glucosidase and α-amylase. This suggests that the watermelon (Citrullus lanatus) juice may have a useful clinical application in the management of diabetes mellitus and its metabolic complications if developed as adjuvant therapy. [ABSTRACT FROM AUTHOR]

Free oxides in soils usually have distinct electrochemical properties, generate both CEC and AEC as a consequence of the adsorption of proton and hydroxyl ions provide structural cementation in the soil. Thus, soil properties are influenced by the occurrence of free oxides. The effect of free oxides on the fixation of K in some soils of southern Nigeria was investigated. Incubation study was done using KCl and the extractability of K applied were examined over a period of time. A series of five sorption treatments (0.11, 0.22, 0.45, 0.90, and 1.8 cmol/kg) were prepared and applied in three sets to 2.5 g soils (15 soil samples per set). The first set of soil samples was extracted with 1 N NH4OAc extractant for K after 1 day of incubation. The second and third sets were extracted with the same extractant after 7 and 42 days of incubation, respectively. The amount of K fixed was determined and the correlation between K fixed and some soil properties was done. The amorphous iron oxides (Feo) correlated significantly (P <.01) with the amount of K fixed (r = 0.68**). Clay also had a highly positive and significant correlation with K fixed (r = 0.75**, P <.01). There was no relationship between the oxides of Aluminum (Alo and Ald) and K fixed, both having r-values of 0.220 and 0.391, respectively. Thus, the ability of these soils to retain K was due to the presence of clay and free iron oxide especially the ammonium oxalate extractable free iron oxide (i.e. amorphous iron oxide). [ABSTRACT FROM AUTHOR]

The suitability of silica sand deposits of Gada and Muvur in Mubi North Local Government Area of Adamawa State, Nigeria for commercial glass production was assessed based on the chemical and physical properties of the silica sand samples collected along the river sides. The test was carried out at National Metallurgical Development Centre (NMDC) Jos. Chemical analysis was carried out using x-ray florescence spectrometer (XRFS) and the physical properties such as the particle size, grain morphology and specific gravity examinations were carried out using mechanical shaker (sieving method), electronic microscope to reveal the shape of the samples and the specific gravity testing machine respectively. The results obtained were assessed and compared with the standard requirements for glass making. Gada had the highest percentage of silica content of 81.00% and Muvur had the lowest percentage of silica content of 79.40%, but all samples are within the acceptable limits for glass making. The iron oxide content in all the samples was found to be high, with highest value of 1.33% for Muvur and lowest value of 1.28% for Gada. However, the iron content for all the samples was above 1% thereby limiting the range of applications to coloured and amber glass manufacturing. The physical properties that is, the grain morphology which was found to be angular with specific gravity of 2.50 for both the samples were found to satisfy the standard requirements for glass making. [ABSTRACT FROM AUTHOR]

Concealed and fossilized geothermal systems are not characterized by obvious surface manifestations like hotsprings and fumaroles, therefore, could not be easily identifiable using conventional techniques. In this investigation, the applicability of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Hyperion data-sets were evaluated in discriminating hydrothermal alteration minerals associated with geothermal systems as a proxy in identifying subtle Geothermal systems at Yankari Park, Nigeria. Feature-oriented principal component selection, spectral angle mapper, linear spectral unmixing were applied to ASTER data based on spectral characteristics of hydrothermal alteration key minerals for a systematic selective extraction of the information of interest. Analytical imaging and geophysics-developed processing methods were applied to Hyperion data for mapping iron oxide/hydroxide minerals and clay mineral assemblages in hydrothermal alteration zones. The results indicate that ASTER and Hyperion could be complemented for reconnaissance stage of targeting subtle alteration mineral assemblages associated with geothermal systems. [ABSTRACT FROM AUTHOR]

Thirty-four core shale samples from the Upper Cretaceous Mamu Formation, southeastern Nigeria, were studied using XRD and geochemical analyses to constrain their provenance, tectonic setting, palaeoweathering and palaeoredox conditions during deposition. X-ray diffraction analysis revealed the presence of clay minerals (kaolinite, illite and illite-smectite mixed layer) and non-clay minerals (quartz and feldspar). The dominance of kaolinite and the high kaolinite/illite (K/I) contents indicate warm and humid climatic conditions during sediment accumulation. The total organic carbon (TOC) content of the shales ranges between 0.31 and 55.34%. The high Chemical Index of Weathering (CIW; mean∼98.8%), Chemical Index of Alteration (CIA; mean∼92%) and Plagioclase Index of Alteration (PIA; mean∼98.7%) for the shales, including a high content of kaolinite, indicate intense chemical weathering in the source area. The positive correlations between V, Cr, Ni, Co, Ga, Cd, Be, Sc, TiO 2 , MgO with Al 2 O 3 and Ba with K 2 O suggest that these elements in the shales are mainly held in clay minerals. The elevated contents of Zr and the high Zr/Cr and Zr/Sc ratios imply that the shales were derived from predominantly felsic source rocks. However, TiO 2 /Zr and Y/Ni ratios suggest a derivation from an admixture of complex felsic and mafic basement rocks. The low average enrichment factor values of Mo (Mo EF), V (V EF) and U (U EF), along with low concentrations of redox-sensitive trace element ratios (Mo/U, Ni/Co, V/Cr and Cu/Zn) and high TOC contents infer oxic conditions during deposition. Furthermore, Fe 2 O 3 –S-TOC relationships, along with DOP T , V/(V + Ni) and Fe 2 O 3 /Al 2 O 3 ratios, suggest dominantly oxic to slightly dysoxic/anoxic conditions during the accumulation of the Mamu Formation shales. Binary plots of K 2 O/Na 2 O ratio versus SiO 2 indicate a passive margin tectonic setting for the shales. • Deposition of the shales occurred under well-oxygenated, shallow water conditions. • Mineralogical maturity and chemical weathering of the shales reflect second cycle sediments. • DOP T and Fe 2 O 3 –S-TOC relationships revealed the elemental variability of the Mamu Shales. [ABSTRACT FROM AUTHOR]