RMZ-Material And Geoenvironment Journal, Slovenia

 Journal

 Using Artificial Neural Network To Predict Dry Density Of Soil From Thermal Conductivity

 Oluseun Adetola Sanuade, Rasheed Babatunde Adesina, Joel Olayide Amosun, Akindeji Opeyemi Fajana, Olayiwola Grace Olaseeni

 2017

Artificial neural network (ANN) was used to predict the dry density of soil from its thermal conductivity. The study area is a farmland located in Abeokuta, OgunState, Southwestern Nigeria. Thirty points were sampled in a grid pattern, and the thermal conductivities were measured using KD-2 Pro thermal analyser. Sampleswere collected from 20 sample points to determine the dry density in the laboratory. MATLAB was used to perform the ANN analysis in order to predict the drydensity of soil. The ANN was able to predict dry density with a root–mean-square error (RMSE) of 0.50 and a correlation coefficient (R2) of 0.80. The validation of ourmodel between the actual and predicted dry densities shows R2 to be 0.99. This fit shows that the model can be applied to predict the dry density of soil in study areaswhere the thermal conductivities are known. 

 Earth Systems And Environment, Springer

 Journal

 Geotechnical And Geochemical Assessments Of Shales In Anambra Basin, Southeastern Nigeria, As Landfill Liners

 Rasheed B. Adesina And Moshood N. Tijani

 2017

The use of landfills as containment for municipal solid waste management has received wide acceptance the world over. Its development in countries like Nigeria is constrained by high cost and scarcity of synthetic liners in the local markets. Exploration of the abundant locally available clay deposits in the country’s sedimentary Basins will prove economical, provided it satisfies the standard specifications for design and construction of landfill liners. This study thus evaluates the suitability of shales from three formations (Enugu, Ameki and Imo) within Anambra Basin of Southeastern Nigeria as liner materials. Geotechnical tests such as particle size distribution, Atterberg’s limits, compaction, coefficient of permeability and consolidation were performed on the shale samples. Geochemical analyses involving the inductively coupled plasma emission spectroscopy (ICPES) and cation exchange capacity (CEC) were also conducted; all employing standard methods. Based on the Unified Soil Classification System (USCS), Enugu and Imo shales contain high-plastic inorganic clay, while Ameki shales comprise low–medium plastic inorganic clay. Coefficient of permeability result ranging from 9.12×10-6 to 2.14×10-6cm/s indicates an increase above the standard specification. Expectedly, the cation exchange capacity (CEC), compressibility and plasticity index of the shales are positively related suggesting strong influence of the geotechnical properties on their sorption potentials. Overall assessment revealed that the high hydraulic conductivity and swelling potentials of the shales are not suitable for natural clay liners. Nevertheless, Enugu and Imo shales can further be stabilized chemically to the desired hydraulic conductivity of liners considering other suitable geotechnical properties and their CECs.

 

 Global Journal Of Geological Sciences

 Journal

 Hydrochemical Assessment Of Groundwater Quality In Sagamu Area, Southwestern Nigeria

 Kareem R.O., Adesina R.B And Adetu O.S

 2016

Groundwater samples from 39 wells in different geological settings in Sagamu area, Southwestern Nigeria were analysed for their hydrochemical properties, to determine their suitability for domestic and irrigation purposes. The samples were subjected to chemical analysis involving the Induced Coupled Plasma Mass Spectrometry (ICPMS) for cation determination, and volumetric analysis to determine the anions. The classification of the groundwater using Piper diagram, Gibbs variation, Wilcox classification and Zhang evolution plot reveals the distribution of groundwater quality in the area. Parameters like Sodium Absorption Ratio (SAR), Magnesium Adsorption Ratio (MAR) Kelly’s Ratio (KR), Permeability Index (PI), Residual Sodium Bicarbonate (RSBC), and chloro-alkaline indices (CAI), were calculated for irrigation purposes. The results were presented as spatial distribution maps for interpretation and further inferences. Comparison of the groundwater quality in the area with local and international standards indicates that 94.9% of the groundwater within the area is generally suitable for domestic and irrigation purposes.

 

 RMZ- Material And Geoenvironment, Slovenia

 Journal

 Hydrogeophysical Investigation Of Groundwater Potential And Aquifer Vulnerability Prediction In Basement Complex Terrain – A Case Study From Akure, Southwestern Nigeria

 Opeyemi J. Akinrinade And Rasheed B. Adesina

 2016

This study provides a model for the prediction of groundwater potential and vulnerability of basement aquifers in parts of Akure, Southwestern Nigeria. Hy­drogeophysical surveys involving very-low-frequen­cy electromagnetic (VLF-EM) profiling and electrical resistivity (ER) sounding, as well as evaluation of hy­draulic gradient using three-point method, were car­ried out. Ten VLF-EM reconnaissance survey traverses, with lengths ranging from 55 m to 75 m, at 10 m station separation, and 12 vertical electrical sounding (VES) stations were occupied. Two-dimensional map of the filtered real component reveals areas of high conduc­tivity, indicative of linear features that can serve as a reservoir or conduit for fluid flow. Interpretation of the VES results delineates three to four geoelectric units. Two aquifer zones were identified, with resistivity val­ues in the ranges of 20 Ωm to 310 Ωm and 100 Ωm to 3,000 Ω m, respectively. Transverse resistance, longi­tudinal conductance, coefficient of anisotropy and hy­draulic gradient have values ranging from 318.2 Ωm2 to 1,041.8 Ωm2, 0.11 mhos to 0.39 mhos, 1.04 to 1.74 and 0.017 to 0.05, respectively. The results of this study identified two prospective borehole locations and the optimum position to site the proposed septic system, based on the aquifer’s protective capacity and ground­water flow properties.

 

 Journal Of Oceanography And Marine Science

 Journal

 Baseline Physico-chemical And Bathymetry Assessment Of Mahin Lake, Southwestern, Nigeria

 Akinrinade Opeyemi J., Adesina Rasheed B., Ogundare Margret O. And Ashiru Olusola R.

 2016

Assessment of baseline physico-chemical parameters and bathymetry mapping of Mahin Lake has been carried out for effective and sustainable utilization, management, conservation, and exploitation of its resources. pH, temperature, dissolved oxygen, electrical conductivity, resistivity, total dissolved solid (TDS), salinity, and surface pressure were determined in situ; while concentrations of calcium, magnesium, sodium, potassium, chloride, nitrate, and phosphate in water samples were determined in the laboratory. Bathymetry map revealed that the deepest portion of the lake is 4.3 m, while surface area and estimated volume of water were 1.82×106 m2 and 4.48×106 m3, respectively. The parameters measured shows considerable spatial variations. Mahin Lake is classified as a freshwater lake, indicating little interaction with the Atlantic Ocean; while its water is classified as ‘soft’ and weakly mineralized considering Ca2+ (0.46 to 1.69 mg/L), Mg2+ (0.55 to 1.83 mg/L), pH (5.05 to 5.5) and electrical conductivity (72.75 to 95.75 μS/cm). With these result, growth, biodiversity, and productivity of marine organisms within the lake are at risk. The low dissolved oxygen concentration (DO, 0.04 to 0.91 ppm) tends towards anoxia status and can possibly cause fauna depletion. Trace anthropogenic impact were identified on the western flank of the lake. The status of the lake provides a guide to further research in determination of its tectonic evolution. Sustainable environmental management system is required to prevent possible anthropogenic activities which can further reduce the quality of Mahin Lake and its associated ecosystem.

 

 Ocean And Coastal Management, Elsevier

 Journal

 Effect Of Coastal Land Use Change On Coastline Dynamics Along The Nigerian Transgressive Mahin Mud Coast

 O.A. Dada, A.O. Agbaje, R.B. Adesina, Y.A. Asiwaju-Bello

 2002

Over the last ten decades, the coastal zone has been experiencing population growth and incomparable developments that are in discordance with the dynamic nature of the coastal system. This makes imperative the understanding of complex processes influencing the coastal system. The present study focused on the coastline changes and associated land use/land cover (LULC) patterns along the ?89 km Mahin mud section of the Nigerian Coast in the Gulf of Guinea of the North Atlantic Ocean during the last 30 years (1987–2017). The study utilized ten multispectral Landsat TM/OLI 8 images in the geographic information system (GIS) environment for the coastline changes and the LULC patterns using maximum likelihood classifier (MLC) algorithm. Net rates of coastline change, on short-term and long-term periods, were calculated from endpoint rate (EPR) and linear regression rate (LRR) statistical methods, respectively. Results showed that the entire Mahin Mud coast is undergoing serious erosion. Over the entire study period (1987–2017), 58% (50.7 km) coastline of the study area experienced retreat. This rapid rate of coastline retreat has triggered land loss of 10.64 km2 to the Atlantic over the last 30 years. The study found that although the changing wave climate has a strong influence on the observed patterns of erosion and accretion along the Mahin mud coast, both marine and anthropogenic processes are acting in concomitance to influence coastal retrogradation along the coast. Therefore to curtail the ongoing coastal retrogradation along the mud coast, there is a need to fashion out the most sustainable approach that will facilitate the realization of the twin objectives of safeguarding the mud coast whilst at the same time maintaining and improving the socio-economic development of the area. Further, there is a need for strengthened spatial planning regulations that would control human activities and specify roles of the various coastal stakeholders in mitigating coastal retrogradation and other related coastal hazards in the study area. Finally, we propose a longterm policy of managed retreat that will curtail communities' exposure to coastal hazards, save lives, and lessen the expenditure of public fund on vulnerable infrastructure and response mechanisms.