Highlights Radioactivity in soil sediments of Iju River was found to be within the limit level. Excess lifetime cancer risks on human and ecosystem found to be higher slightly in some sites. Activity utilization index from gamma radiation of natural radionuclides found to be within the permissible level.

Geophysical analysis was carried out to evaluate the challenges encountered in land seismic exploration within the study area. This analysis cuts across various stages in land seismic acquisition. These stages include the following: the availability of the prospect map as originally planned by the prospect owners—the client, the desk study and planning of this map by the seismology section (planning seismologist) for acquisition convenience and the field implementation of the acquisition which the survey, drill and recording (preloading, shooting, swath move, line check, LAUX crew and recording platform) sections carried out. The challenges observed included environmental challenges, noise interference, weather conditions (statics or electrostatics interference), line break, faulty equipment, wrong detailing, cake or expired explosives, poor or compromised supervision, security and permit challenges. These challenges are peculiar to Nigeria due to inadequate implementation of policies that guide human settlements and activities. Nigeria is within the climate region where most at times it is very impossible to control natural events like cloudy weather, rainfall, thundering and lightening. As such, the problem of static charges interfering with acquired seismic data becomes inevitable, mostly during the rainy season. Almost total dependency on imported technology and lack of readily available experienced manpower also contribute to these challenges, most especially when it has to do with proper inspection of equipment and materials required for the acquisition and supervision processes. Approaches to follow to minimize the observed challenges were equally highlighted.

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The reality of aerosol loading is synonymous to climate change. According to National Aeronautics and Space Administration (NASA) imagery, aerosol deposition over West is very high compared to other parts of the world. The danger of aerosol loading is grave when in excess and little effort is made by government in the West Africa region to embark on ground measurement of aerosol optical depth (AOD). In this paper, the satellite measurement (Multi-angle Imaging Spectro-Radiometer) was used to obtain the aerosol optical over the research area. The computational analysis was carried out using the MATLAB software. The percentage of increase of aerosols loading was high in 2001, 2005 and 2011 that was 5.7%, 24.5%, 8% and 11.1%. Cumulatively increase of aerosol loading within 15 years was 11.7%. It is therefore recommended that government in the region should be more committed to ground measurement of AOD to ascertain the state of air pollution in the lower troposphere.

The key factor in a successful oil field development plan is understanding the reservoir. The effectiveness of oil extraction is determined by variations in the reservoir, specifically the distribution of porosity and permeability. To create an accurate model of the reservoir, the vertical distribution of its qualities must be determined and separated into flow units, each with its own unique characteristics that affect fluid flow. By identifying these flow units, the preferred flow zones can be discovered. The aim of this study is to identify the number and distribution of hydraulic units, their important characteristics, and the flow performance in two specific wells in the Niger Delta, Nigeria, using the Modified Lorenz Plot (MLP) method. In the hydrocarbon-rich intervals of the wells, a total of 18 flow units were found, with 12 in Well 1 and 6 in Well 2. The number of flow units indicates the level of heterogeneity in the reservoir. This study showed that the Modified Lorenz Plot (MLP) is an efficient and low-cost method for defining petrophysical flow units. This research study aims to transform the conventional approach to reservoir characterization by conducting a thorough analysis of hydraulic flow units in sandstone reservoirs located in the complex geological setting of the Niger Delta, Nigeria. By examining the hydraulic properties of reservoir rocks, the study seeks to gain a better understanding of subsurface fluid flow behavior and the potential for hydrocarbon accumulation.