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The Bida and Anambra Basins are major inland sedimentary basins located in the central and southern part of Nigeria with possible hydrocarbon potential but lack exploratory data. The present study aims at providing base line information on the thermal regime of the sedimentary basins, which would significantly contribute to its hydrocarbon prospect, investment opportunity and exploitation. The spectral analysis of the aeromagnetic anomaly data from the southern Bida Basin, northern Anambra Basin and adjacent basement complex terrain reveals the Curie point depth (CPD), geothermal gradient and heat flow in the region. The data reveals a CPD that varies between 19 and 30 km while the geothermal gradient is from 23 to more than 44 °C/km with heat flow values ranging from 50 to 109 mW/m2 in the southern Bida Basin. In the northern Anambra Basin, the CPD values range from 6.8 to 20 km and the heat flow values vary between 59 mWm2 and 109 mWm2, with a localized shallow CPD value of less than 6.8 km and associated high heat flow of 109 mWm2 in the central part of the basin. The delineated thermal patterns in the Bida and Anambra Basins are interpreted to be associated with the intrusions and the presence of deep-seated rift. The interpretation of the aeromagnetic data shows good agreement with the land surface temperature obtained from remote sensing data of the study area. The distribution of heat patterns in the southern Bida and northern Anambra Basins have implications for geothermal, source rock maturation and hydrocarbon generation evaluation of the basins. [ABSTRACT FROM AUTHOR]

This study investigates the spatiotemporal distribution and trends of extreme temperature events across four climatic zones in Nigeria. These were done by analyzing daily maximum and minimum temperature data from 20 synoptic stations for 1983–2017 at 0.5° × 0.5° resolution obtained from NASA Power Archive. The study evaluated trends in 13 extreme temperature indices recommended by ETCCDI and categorized them into intensity and frequency indices for warm and cold events using linear regression and the modified Mann–Kendall test. Results revealed increasing trends in indices related to extremely warm temperatures like annual maximum temperatures (TXx), warm days (TX90p), warm nights (TN90p), summer days (SU25), tropical nights (TR20), and warm spell duration (WSDI), across most regions, indicating more frequent and intense warm extremes. Conversely, decreasing trends were observed in indices associated with extreme cold temperatures including cold days (TX10p), cold nights (TN10p), and cold spell duration (CSDI). Regional and seasonal variations were also observed, with the Sahel and Savannah regions experiencing more pronounced warming trends compared to the Forest and Coastal regions. Some indices exhibited stronger warming trends during the wet season and cooling trends during the dry season. The findings contribute to understanding climate change dynamics in Nigeria and emphasize the urgent need for adequate mitigation and adaptation strategies to address challenges posed by rising temperatures across the different climatic zones in Nigeria. [ABSTRACT FROM AUTHOR]

In this study, net radiation and temperature data were collected from the Nigeria Meteorological Agency, Lagos, covering a period of 1983–2013. The study uses a multiple layer perceptron (MLP) model of artificial neural network (ANN) with three algorithms namely the Gradient Descent, Conjugate Gradient, and Broyden–Fletcher–Goldfarb–Shanno for the prediction of net radiation using the temperature series as input variables in place of commonly used empirical statistical methods. The investigation is conducted in a tropical region where 16 meteorological stations spatially distributed across the four climatic regions of Nigeria viz semi-arid (SAR), sub-humid dry (SHD), sub-humid humid (SHH), and humid (HUM) regions were used as a case study. Analyses showed that minimum temperature has a greater positive impact on net radiation than maximum temperature. This has been attributed among other factors to have contributed to higher magnitudes of net radiation in humid regions than those of arid regions. Meanwhile, the performance assessment of the ANN models using the refined index (dr) metric showed that among the three models proposed, the MLP-BFGS model performed best having maximum values of 0.91 in the SAR, 0.65 in the SHD, 0.80 in the SHH, and 0.88 in the HUM regions. It also has the lowest error analysis with magnitudes of root mean square error values of 7.92 W/m2 in the SAR, 9.95 W/m2 in the SHD, 12.91 W/m2 in the SHH, and 8.73 W/m2 in the HUM regions. Finally, it can be inferred from the results that MLP neural networks with the BFGS algorithm can predict net radiation accurately better than any empirical statistical methods over Nigeria. [ABSTRACT FROM AUTHOR]

Tropospheric scintillation depends significantly on any location's prevailing weather condition, and its variation must be statistically analyzed to ensure accurate fade margin determination. This study examines the distribution of Ku-band amplitude scintillation across selected locations in tropical Nigeria. Eight years of daily averaged data of surface temperature and relative humidity were employed for computing scintillation intensity (σ) and amplitude (χ) using international telecommunications union recommended model across eighteen (18) stations, that are subdivided into four (4) regions and spread over tropical Nigeria. The data, spanning January 2010 to December 2017, were obtained from the archive of the European center for medium-range weather forecasts (ECMWF) with a resolution of 0.125° by 0.125°. Three (3) years of in-situ data of concurrently measured satellite radio beacons and primary radio-climatic parameters at Akure (7° 17′ N, 5° 18′ E, 358 m), South-west Nigeria, were employed for comparison and validation. Statistical analyses involving time series, probability density, and cumulative distribution functions were performed on the scintillation dataset annually. Results indicate that the magnitude of tropospheric amplitude scintillation varies across different locations; nevertheless, it exhibits a similar distribution pattern characterized by the generalized extreme value (GEV) probability density function (pdf). The study has shown the need to incorporate the scintillation component into the fade mitigation architecture of telecommunication systems in tropical Nigeria while considering its regional variability. Also, experimental validation of the observations raised in this study should be encouraged at all the locations for better prediction accuracy. [ABSTRACT FROM AUTHOR]

The Patti Formation which consists of sandstone and shale offers the best potential source beds in the Bida Basin. This inland basin is one of the basins currently being tested for hydrocarbon prospectivity in Nigeria. Fresh samples of shale from Agbaja borehole, Ahoko quarry and Geheku road cut were analysed using organic geochemical and palynological techniques to unravel their age, paleoecology, palynofacies and source bed hydrocarbon potential. Palynological data suggest Maastrichtian age for the sediments based on the abundance of microfloral assemblage; Retidiporites magdalenensis, Echitriporites trianguliformis and Buttinia andreevi. Dinocysts belonging to the Spiniferites, Deflandrea and Dinogymnium genera from some of the analysed intervals are indicative of freshwater swamp and normal sea conditions. Palynological evidence further suggests mangrove paleovegetation and humid climate. Relatively high total organic carbon TOC (0.77–8.95 wt%) was obtained for the shales which implies substantial concentration of organic matter in the source beds. Hydrocarbon source rock potential ranges from 0.19 to 0.70 mgHC/g.rock except for a certain source rock interval in the Agbaja borehole with high yield of 25.18 mgHC/g.rock. This interval also presents exceptionally high HI of 274 mgHC/g.TOC and moderate amount of amorphous organic matter. The data suggests that in spite of the favourable organic matter quantity, the thermal maturity is low as indicated by vitrinite reflectance and Tmax (0.46 to 0.48 Ro% and 413 to 475 °C, respectively). The hydrocarbon extracts show abundance of odd number alkanes C27–C33, low sterane/hopane ratio and Pr/Ph > 2. We conclude that the source rocks were terrestrially derived under oxic condition and dominated by type III kerogen. Type II organic matter with oil and gas potential is a possibility in Agbaja area of Bida Basin. Thermal maturity is low and little, or no hydrocarbon has been generated from the source rocks. [ABSTRACT FROM AUTHOR]

The Maastrichtian Gombe Formation is located within one of the inland basins of Nigeria (Gongola Basin). Surface and borehole samples of coal and interbedded shale of this formation were evaluated to determine the organic matter richness, quality, maturity, source and depositional environment through organic geochemical techniques such as total organic carbon (TOC) determination, Rock–Eval pyrolysis, chromatography and organic petrography. The genetic potential and average TOC value of the coals, shales and coaly shales are 38.03 wt%, 3.14 wt% and 12.1 wt%, respectively, indicating moderate-to-good source potential. HIs are less than 200 mgHC/gTOC for all the samples indicating Type III kerogen for most of the samples (gas prone) and plant contributions from terrestrial sources. The source rocks were characterized by high molecular weight n-alkanes which range from C10–C41 in the coals and C9–C41 in the shales. The n-alkanes distributions in the coals maximize at C29 indicating terrestrial sourced organic matter, while the shales maximize at C16 and C29 indicating mixed sources. Pr/Ph of the coals and shales ranges from (2.15–3.51) to (0.95–2.37), respectively, suggesting fluvio-deltaic deltaic and coastal swamp depositional environments. The predominance of pristane over phytane suggests humic origin of the organic matter. The sterane/hopane values (< 0.6) indicate incorporation of bacterial inputs commonly associated with terrigenous organic matter in the coals. The CPI is greater than unity, Tmax is generally < 435 °C and vitrinite reflectance less than 0.55 Ro for most of the samples and suggest the samples are of low maturity status to expel liquid hydrocarbon. [ABSTRACT FROM AUTHOR]

The problem of leveraging social media for establishing and sustaining consistent policies, procedures and methods of online communication can be challenging for busy professionals. To address this issue and to contribute to the literature we develop our research model to gain a deeper upstanding of the factors that influence social media continuance usage. The theoretical background for our research model are technology acceptance model and diffusion of innovation. We collected our data from college students that are enrolled in a large public university located in North America. We analyze our data using confirmatory factor analysis and structural equation modeling. The results of our data analysis show that ease of use, usefulness, and satisfaction of social media have a positive and significant influence on social media continuance usage. Also, our results show that relative advantage, compatibility, information quality, and risk of social media have a positive influence on the usefulness of social media. We discussed the results implications for theory development and practice. [ABSTRACT FROM AUTHOR]

The Gongola Basin forms one of the inland Cretaceous to tertiary sedimentary basins in Nigeria with relatively unknown petroleum system. In this study, the investigated source rock intervals of the Maastrichtian Gombe Formation are located at the Maiganga coal mine, near Gombe, Gongola Basin, Nigeria. The exposed part of the mine consists of about 35-m thick coarsening upward section with the basal part made up of coal and shale interbeds while the upper part consists of siltstone and sandstone and probably deposited in fluvio-deltaic environment. The coal and interbedded shale appear most prospective source rock facies in the formation and were evaluated with respect to their hydrocarbon source rock potential. The organic geochemical results showed high TOC for the coals (37.71-65.29 wt%) and moderate organic carbon concentration (1.19-4.81 wt%) for the shales. S values ranges from 57.96 to 103.21 mgHC/g rock and 0.51-6.22 mgHC/g rock for the coal and shales, respectively. The HI is less than 200 mgHC/gTOC in all the coal and shale samples suggesting Type III kerogen and predominant plant contributions from terrestrial sources. Consequently, gaseous hydrocarbon potential is exhibited in the source beds. The organic petrography shows vitrinite as dominant maceral followed by inertinites and liptinites with inorganic minerals like pyrite and kaolinite. The Tmax is less than 435 °C in all the samples indicating pre-oil window stage; this is corroborated by the Romax value ranging from 0.45 to 0.55 %. Plot of PI against Tmax indicates low level organic matter conversion while the vitrinite reflectance values suggest a sub-bituminous coal. The study suggests that the investigated coal and shale samples constitute good source rock and have potential for gas. The generally low HI in the coals and the associated shales indicate more allochthonous and hydrogen poor organic matters in the source beds. Maceral composition of the coals suggests wet swamp environment and predominance of arborescent vegetation type. At present level, the organic matters are immature to marginally mature deeper level equivalents might have generated gas. [ABSTRACT FROM AUTHOR]