The relationships between density and velocity are important in many geological analyses that involve rock property parameters. However, the accuracy of the results is often limited when there is a verbatim application of generalized rock property relationships. Many studies in the Niger Delta Basin suffer from this limitation. As a way forward, well logs in the Niger Delta were used to derive lithology-specific coefficients that can be applied in density-velocity transforms that make use of the Gardner equation. Whereas the default coefficient (a) and exponent (b) in the original Gardner equation are 0.31 and 0.25, respectively, fitting the Gardner curve to local data results in a coefficient value of 0.33 and 0.29 for shales and sands, respectively, when the exponent is kept at the default value. Comparing measured density data with estimates obtained from sonic velocities using the original Gardner equation gives a regional mean absolute deviation of 0.13 g/cc while those of the newly derived local coefficients do not exceed 0.05 g/cc giving an improvement of over 60% in the accuracy of estimated rock properties.

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The study determined the variations of carbon dioxide and temperature within south-south and south-eastern parts of Nigeria from January 2009 to December 2014. The study specifically focused on the perceived impacts posed by climate change on environment within these regions due to carbon dioxide emissions. The results revealed that rise in temperature within these regions could significantly be dependent on the increase in CO2 emissions and other greenhouse gases. It was observed that CO2 emission increases continuously over all the years of study at each station. This could be attributed to high percent occurrences of urban warming experienced in these areas. The results also revealed that various impacts of climate change and weather within these regions could be due to high emission of carbon dioxide caused by fossil fuel, gas flaring etc found within these regions. It was also observed from the results that no gaseous pollutant or greenhouse gas can have 100% influences on climatic parameters like temperature.

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The emergence of COVID‐19 brought with it panic and a sense of urgency causing governments to impose strict restrictions on human activities and vehicular movements. With anthropogenic emissions, especially waste management (domestic and municipal), traffic and industrial activities, said to be a significant contributor to ambient air pollution, this study assessed the impacts of the imposed restrictions on the concentrations and size distribution of atmospheric aerosols and concentration of gaseous pollutants over West African sub‐region and seven major COVID‐19 epicenters in the sub‐region. Satellite retrievals and reanalysis datasets were used to study the impact of the restrictions on Aerosol Optical Depth (AOD) and atmospheric concentrations NO 2 , SO 2 , CO and O 3 . The anomalies were computed for 2020 relative to 2017‐2019 (the reference years). In 2020 relative to the reference years, for area‐averaged AOD levels, there was a consequential mean percentage change of between ‐6.7 ± 21.0 % and 19.2 ± 27.9 % in the epicenters and ‐10.1 ± 15.4 % over the sub‐region. The levels of NO 2 and SO 2 also reduced substantially at the epicenters, especially during the periods when the restrictions were highly enforced. However, the atmospheric levels of CO and ozone increased slightly in 2020 compared to the reference years. This study shows that “a one cap fits all” policy cannot reduced the level of air pollutants and that traffic and industrial processes are not the predominant sources of CO in major cities in the sub‐region.