Scholarly works in the Department of Geophysics
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Item 2D Geo-electrical Resistivity Imaging of Clay Deposit in Agbonmwoba Village, Edo State, Nigeria(IISTE (International Institute for Science, Technology and Education), 2020-10-31) Osisanya, O.W.; Macpaul, A.P.; Isaac, K.A.; Folorunso, A.Z.This study involves delineation of clay deposits in Agbonmwoba village area of Obaretin town, Edo state using 2D geo-electrical resistivity tomography technique to image the extent and economic quantity of the deposit, in order to appraise its commercial viability. The Wenner-Schlumberger electrode configuration was employed in five different locations within the study area, and a total of ten (10) Wenner-Schlumberger soundings were acquired in the area with a spread length of 200m along each traverse. The field data was inverted using the Earth Imager 2D inversion software program. Low resistivity geologic formations (ρ < 50 Ωm) were interpreted as clay formations using knowledge of regional geology of the area as reported from previous studies. Along traverses 1, 2 and 8 sampled at old Sapele road Ekiosa clay deposits was imaged at depth of 8.9-15m at lateral spread of 30m and 70m in TR1, 8.9-17.9m in TR2 and 4m in TR8. In traverses 3 and 4 sampled along Presco road in Obaretin, clay deposits were imaged at 8.9m from the surface in TR3 and 8.9-10m in TR4 at lateral spread of 70m and 100m respectively. Traverses 5, 6 and 7 were sampled at Agbonmwoba primary school, and clay deposit was imaged at 17.9-21m in TR5 at lateral spread of 80-90m, clayey sand was imaged at 7.5m (< 8.9m) and sand deposit was imaged at 24.0m (< 26.8m) which underlies clay. In TR6, clay deposit was imaged at 8.9m from the surface and in TR7, clay deposits were imaged in layers at profound depths >30m at lateral spreads of 20-80m and 130-160m respectively. In TR8 clay deposit was imaged at 4m from the surface. In TR9 clay deposit was imaged at 8.9- 17.9m at lateral spread of 90-110m and in TR10 clay deposit was imaged at 17.9-20m at lateral spread of 40m and 100-120m respectively. This results show that clay deposits imaged along traverses 1, 2, 4, 5, 9, and 10 are located at proximal depths within the subsurface and this implies that the subsurface geology distribution along these profiles is slightly homogenous in lithology, and clay deposits along these traverses are exploitable, while clay deposits along traverses 3, 6 and 8 are found at the surface (0-8.9 m) as thin clay deposits and therefore not commercially viable for exploitation. Clay deposits imaged in traverse 7 was relatively massive in size (subsurface distribution) and was observed at profound depth of 26.8-35.7m (> 30m), which makes it commercially viable for exploitation compared with other traverses. The results was correlated with borehole lithologic section drilled along TR5 in the area and both sections agreed in lithologic sequence with respect to depth. Thus, 2D resistivity imaging gives a better vertical and lateral view of subsurface layers than geo-electric sections computed from 1D models, because of its ability to give a continuous record of subsurface formations at greater deptItem 3-D Seismic Structural Interpretation of High Field Offshore Western Niger Delta.(The Journal of Applied Sciences and Environmental Management (JASEM), 2021) ADEBAYO, S.S.; AGBALAGBA, E.O.; KORODE, A.I.; FAGBEMIGUN, T.S.; OYANAMEH, O.E.; OSISANYA, O.W.Seismic Structural interpretation of subsurface system is a vital tool in mapping source rocks and good trapping system which enhances good understanding of the subsurface system for productive drilling operation. This study is geared towards mapping the structural traps available within the hydrocarbon bearing zones of the “High field” with the use of well log and 3D seismic data. Seven horizons (H1, H2, H3, H4, H5, H6 and H7) were identified on well logs using gamma ray log and resistivity logs. Nine (9) faults were mapped on seismic sections across the field, two (2) of which are major growth faults (F1 and F2), two (2) synthetic faults (F3 and F7) and five (5) antithetic faults (F4, F5, F6, F8 and F9). Rollover anticlines which are structural closure and displayed on the depth structural maps suggest probable hydrocarbon accumulation at the down throw side of the fault F1. Structural interpretation of high field has revealed a highly fault assisted reservoir which depicts the tectonic setting of Niger Delta basin.Item 3D TIME-LAPSE GEOPHYSICAL IMAGING OF FERTILIZER-INDUCED SOIL AND GROUNDWATER CONTAMINATION IN OGHARA, DELTA STATE, NIGERIA(Zibeline International Publishing, 2025-07) Ozobeme, A.A.; Osisanya, W.O.; Airen, O.J.; Eyankware, O.M.; Iluobe, E.O.Fertilizer contaminants can persist in subsurface environments, making remediation efforts costly and time consuming, particularly in areas with shallow aquifers and permeable soils. This study applied time-lapse geophysical methods to assess fertilizer-related soil and groundwater pollution in agricultural regions of Oghara, Delta State, Nigeria. Eight 2-D electrical resistivity imaging (ERI) surveys were conducted, Including 16 grid-aligned lines across the Presco lowland and upland areas which were collated to form the 3 D models, along with a control line. Data were processed using RES3DINV and ZondRes3D to produce the 3-D resistivity models. Three-dimensional slices illustrated the downward migration of contaminants over time. Analysis of time-lapse data showed maximum vertical migration rates of 216.7 cm/month and horizontal rates of 750.0 cm/month at the initial site. At the second site, rates reached 122.5 cm/month vertically and 500.0 cm/month horizontally. Taking into account local hydrological and geological conditions, the contaminant plumes are projected to reach the dry sandy layer within 0.5 to 1 year.Item A COMPREHENSIVE ANALYSIS OF SOIL AND WATER CONTAMINATION NEAR AUTO MECHANIC WORKSHOPS IN WARRI AND ENVIRON SOUTH-SOUTH, NIGERIA(Zibeline International Publishing, 2023) Aladin, A.E.; Ekewenu, E.E.; Osisanya, W.O.The pH values of soil samples collected from the topsoil to a depth of 50cm range from 5.78 to 6.64, with an average of 6.284, indicating slightly acidic soil. Water samples near auto-mechanic workshops fall below NSDWQ and WHO standards. Soil heavy metal levels mostly meet ACV and Dutch guidelines, except for Iron (Fe), Copper (Cu), Zinc (Zn), Cadmium (Cd), and Chromium (Cr). Soil contamination analysis shows a high to extreme degree of contamination, likely from the auto-mechanic workshop. Positive correlations between metal pairs suggest a common source and transport to the soil. Principal Component Analysis (PCA) of soil samples reveals Cu, Zn, Fe, Ni, and Pb as dominant metals, while Ni-Cr shows negative correlations with others. In water samples, Cu, Cd, and Co dominate, indicating a different contamination source. Soil and water samples generally meet NSDWQ and WHO standards, but Total Dissolved Solids (TDS), Electrical Conductivity (EC), and Salinity exceed these standards. Understanding these findings is crucial for managing and mitigating contamination risks near auto-mechanic workshopsItem Aeromagnetic Interpretation of Basement Structures and Geometry in Parts of the Middle Benue Trough, North Central, Nigeria(Bilingual Publishing Co., 2022-11-30) Esho, O.O.; Osisanya, W.O.; Ibitoye, T.A.; Ajibade, F.Z.; Tokunbo, S.F.The research of an analysis of aeromagnetic data collected in the middle Benue Trough in north-central Nigeria is presented. A detailed analysis of basement structures is conducted in order to identify regions with high hydrocarbon potential that is different from those discovered by earlier researchers. Aeromagnetic data were filtered by using the Butterworth and Gaussian filters, transformed by engaging the reduction to the equator technique, and subsequently enhanced. To estimate magnetic basement depths at various places throughout the basin, the Euler deconvolution depth weighting approach was used. Eleven (11) sub-basins with depths ranging from –2000 m to –8000 m were also identified by Euler’s findings. The sub-basins trend in the NE-SW direction while the average sediment thickness is found to be more than 3 km. The extracted structural features indicate areas like Kadi Blam and Kado areas in the southeastern part and Ogoja and Obudu in the southern part of the study area as regions with high structural densities. These areas coincide with the areas delineated as the sub-basins. The cross-sections generated reveal depressions caused by the action of some tectonic activities in the area. This study identified undulating basement topography believed to be due to tectonic activities as well as five areas that are possible targets for hydrocarbon exploration.Item AN IN-DEPTH STUDY OF HEAVY METALS IN SOILS AROUND SELECTED WASTE DUMPSITES IN PARTS OF SOUTHERN NIGERIA USING HEAVY METAL INDICES AND MULTIVARIATE STATISTICAL ANALYSIS(African Journals OnLine, 2025) Osisanya, W.O.; Agbalagba, O.E.; Agho, I.O.; Eyankware, M.O.; Iduseri, O.MA detailed study was conducted around waste dumpsite in the study area, to evaluate the levels of heavy metals in the soil. Soil samples were collected at twenty (20) different locations within waste dumpsites for the study. The heavy metals (zinc (Zn), chromium (Cr), copper (Cu), lead (Pb), cadmium (Cd), mercury (Hg), nickel (Ni), arsenic (As), and iron (Fe)) were analyzed using atomic absorption spectrometry (AAS). The resulting data was analysed using principal component analysis (PCA), Pearson correlation, and the heavy metal indices: Potential Ecological Risk (ERI), Geoaccumulation Index (Igeo), Contamination Factor (CF), and Nemerow Pollution Index (PNI). Thesoil contain the heavy metals: zinc (Zn), chromium (Cr), copper Cu, Pb, Cd, Hg, Ni, As, and Fe. Their concentrations, inorder 9.28 to 60.1 mg/kg for Zn, 4.4 to 14.39 mg/kg for Cr, 5.4 to 21.39 mg/kg for Cu, 6.07 to 17.5 mg/kg for Pb, 0.04 to 1.5 mg/kg for Cd, 0.0001 to 0.003 mg/kg for Hg, 7.28 to 20.38 mg/kg for Ni, 0.0001 to 0.003 mg/kg for As, and 1020 to 16540 mg/kg for Fe,The Igeo data indicated that all samples fell within the range of 0 to 2, implying that the sediment quality was largely unpolluted. The PNI yielded a diverse array of results within the study area, PC1 has a loading percentage of 77.8%, PC2 has a loading percentage of 44.4%, PC3 has a loading percentage of 33.3%, and PC4 has a loading percentage of 11.1%. This loading signifies the element's importance in the contribution of pollution within elements and to the soil. Further deductions from soil samples results that was compared to World Health Organization (WHO), and Department of Petroleum Resource (DPR), permissible limit suggested that all samples were below the permissible limit except for Cd, that its concentration was above WHO limit at some locations namely; DO/ 02, 03, 04, 05, 06, 08, 09, 10, 12, 13,and 18, this could be attributed to anthropogenic activities within the study area. These findings can serve as a valuable resource for those responsible for managing dumpsites, aiding in the prevention of heavy metal soil contamination.Item An Integration of Geophysics and Petrophysics in Study of Rock at Elete, Lokoja Southwestern Nigeria.(European Centre for Research Training and Development -UK, 2023) Shaibu, Ojoka B.; Osisanya, O. Wasiu; Saleh, A. Saleh; Asarhasa, E. Peter; Okpala, Emeka C.Granitic Gneiss and Banded Gneiss make up the bulk of the local rock types, and quartz veins are the most common intrusions seen there. Tectonic upheavals in the earth's crust are responsible for the region's structural features, including as foliations, folds, joints, and fissures. The goal of this research is to integrate several scientific techniques to subsurface structure definition. For this study, 16 Vertical Electrical Sounding (VES), petrophysical study, and background knowledge of geology were used to delineate subsurface rock. The Schlumberger array with a maximum electrode separation of 300m was employed for VES. Elete's true aquifer resistivity map shows that the South-Eastern and North-Eastern axis has relatively low resistivity values, which may indicate the presence of an aquiferous zone, while the North-Central and Southern regions have a wider range of resistivity values, which may not be consistent with a water-bearing zone. Additionally, petrographic analysis of the rock reveals that the mineral composition of Granitic Gneiss is Quartz (41.72%), Plagioclase (10.79%), Biotite (25.17%), Muscovite (19.42%), and Opaque (2.87%). While biotite makes up the granite gneiss. Biotite (45%), Muscovite (9.93%), Quartz (36.87%), Plagioclase (4.26%), and Opaque (3. 55%).Hydrogeologically, it stands to reason that Elete and its surroundings are situated in a region with medium to good groundwater potential based on the information at hand and the results of the geophysical investigation. Weathered/fractured basements are anticipated to contain productive aquifers.Item Application of Aeromagnetic and Remotely Sensed Data in Mineral Exploration in Parts of Ife-North, Osun State, Southwestern Nigeria(Department of Chemical Engineering, University of Benin, Benin City, Nigeria, 2022-12) Osisanya, O.W.; Shaibu, O.B.; Abolarin, O.M.; Eyankware, M.O.; Okpala, E.C.This paper analysed aeromagnetic data over parts of the Ilesa schist belt of Nigeria with a view to assessing the sub surface structural settings that might favour mineralisation in the study area using aeromagnetic data and satellite remote sensing imageries. The subsurface lineaments were detected and traced out from the maxima of horizontal gradient magnitude, peaks of analytical signal magnitude. The structural trends of the composite lineament map show predominant lineament directions; NE-SW, NNE-SSW, E-W, and NW-SE. These trends were in agreement with the major regional tectonic trends of Southwestern Nigeria. The interpretation of the aeromagnetic dataset gave an insight into the regional geology and structural trends of the area. The derived lineaments may serve as a reference for future geological and structural mapping. Based on the information gathered so far, the study area shows potential for presence of both primary and alluvial/eluvial gold deposits.Item Application of Aeromagnetic and Remotely Sensed Data in Mineral Exploration in Parts of Ife-North, Osun State, Southwestern Nigeria(Department of Chemical Engineering, University of Benin, Benin City, Nigeria, 2022-12) Osisanya, O.W.; Shaibu, O.B.; Abolarin, O.M.; Eyankware, M.O.; Okpala, E.C.This paper analysed aeromagnetic data over parts of the Ilesa schist belt of Nigeria with a view to assessing the sub surface structural settings that might favour mineralisation in the study area using aeromagnetic data and satellite remote sensing imageries. The subsurface lineaments were detected and traced out from the maxima of horizontal gradient magnitude, peaks of analytical signal magnitude. The structural trends of the composite lineament map show predominant lineament directions; NE-SW, NNE-SSW, E-W, and NW-SE. These trends were in agreement with the major regional tectonic trends of Southwestern Nigeria. The interpretation of the aeromagnetic dataset gave an insight into the regional geology and structural trends of the area. The derived lineaments may serve as a reference for future geological and structural mapping. Based on the information gathered so far, the study area shows potential for presence of both primary and alluvial/eluvial gold deposits.Item Application of Geophysical Methods in the Determination of Pb-Zn Mineralization in Abakaliki, Parts of the Southern Benue Trough, Nigeria(IJESKA / DergiPark, 2024-08) Ighrakpata, C.F; Osisanya, W.O.; Ajibade, F.ZTo identify Pb-Zn mineralization in the Abakaliki province, an integrated strategy was used for the objective of this study. Particularly in the Nsuba, Oputumo, Amenyi, Nsobo, and Opuitumo lodes. This investigation was conducted using two methods: the resistivity method (Dipole dipole configuration) and induced polarization (IP). The apparatus utilized for this research is the Abem Terrameter SAS 4000. There were ten (10) Dipole dipole arrays installed in the research region, with electrode spacing ranging from five to twenty meters in a NW-SE direction and a maximum spread of two hundred meters. Findings from the study suggested that mineralized zones, resistivity values ranging from 0.4 to 1354 Ω-m and chargeability values from -877 to 813 ms were found. Positive magnetic anomalies were found in areas below the ground that had unusually high chargeability and relatively low resistivity structures. This suggested that Pb-Zn minerals might be present. The mineralization, characterized as a mildly disseminated stockwork, leans towards a relatively epigenetic nature.Item Application of high resolution aeromagnetic data for determination of depth to magnetic sources using source parameter imaging in Niger State, Nigeria(Scientific Publishing House, 2025) Sunday, I. O.; Osisanya, W.O.; Saleh, A.S.; Eyankware, M.O.; Chukwusa, F.O.Source Parameter Imaging (SPI) is a pivotal geophysical technique, particularly in aeromagnetism, for delineating subsurface geological structures through the analysis of magnetic anomalies. This study applies SPI to high-resolution aeromagnetic data over Baro and its surrounding areas in Niger State, Nigeria, to estimate the depth to magnetic sources. The research emphasizes the characterization of magnetic sources in terms of depth, geometry, dip, and susceptibility contrast. Data processing techniques, including regional field removal, residual anomaly mapping, and reduction to the magnetic equator, were employed to enhance data accuracy and interpretability. The findings reveal significant variations in sedimentary thickness, suggesting potential hydrocarbon reservoirs, particularly in the northern region, characterized by deeper basins. This study underscores the necessity of further exploration, integrating advanced seismic studies and drilling, to assess the hydrocarbon potential accurately. The SPI-derived insights provide a valuable framework for strategic hydrocarbon exploration in Nigeria's interior basins, contributing to the nation's energy security and economic growth.Item Application of One Dimensional Geophysical Investigation on Proposed Dam Project, Iyah Gbede, Kogi State, Nigeria(International Organization of Scientific Research, 2021) Olabode, O.O.; Oyanameh, O.E.; Idowu, D.O.; Osisanya, O.W.; Korede, A.I.Foundation designs planning is very critical in engineering works, therefore geophysical investigation was carried out for foundation design of a proposed Dam at IyahGbede, Ijumu Local Government Area of Kogi State with a view to deduce and enhance the knowledge of the near subsurface integrity of the area for engineering structures.Electrical Resistivity method was adopted to conduct the survey for detail and distinct result. The aim of the exercise was to determine the soil properties of the subsoil layers that constitute the foundation soils and their competence as foundation soils for a dam site establishment. Traverse lines were established along E-W direction and six (6) Vertical Electrical Sounding points (VES) which is one dimensional in prospect, werelaid which to reveal the subsurface property of the area.The VES curves types are AA,AH, HA and KH,which depicts that the investigated site is competent for the proposed dam project.Item Application of second‑order geoelectric indices in determination of groundwater vulnerability in hard rock terrain in SW. Nigeria(Springer Nature, 2023-09-22) Olumuyiwa, Victor A.; Osisanya, Wasiu O.; Eyankware, Oghenenyoreme . M; Korode, Akinjide I.; Ibitoye, Taiwo A.The application of the VES geophysical technique to investigate groundwater potential and the aquifer vulnerability was carried out at Akure, southwestern part of Nigeria. Sixteen (16) VES points were selected using a Schlumberger array applied for the conduction of the VES. The ABEM Terrameter SAS 1000 was used and the maximum current electrode spacing (AB/2) was 100 m. A partial curve matching technique and computer iteration technique were applied in the interpretation of data using WINRESIST software, while Groundwater Modeling System (GMS) software was used to model the groundwater flow direction. The study revealed the presence of two to four layers of curve types, which include H (69%), HKH (19%), A (6%), and QH (6%) respectively. The second-order geoelectric parameters include longitudinal conductance (S), average transverse resistance (Tr), average longitudinal resistance (ρL), coefficient of anisotropy (λ), reflection coefficient (Rc), and resistivity contrast (Fc). The estimated aforementioned parameters range 0.004–1.03, 659.6–12,416.6 Ω/m2, 28.21–267.4 Ω-m, 58.82–303.26, 1–1.5, 0.33–0.97, and 2.01–57.33, respectively. The distributions of these parameters are revealed by the contour maps, which aid in the delineation of zones with different layer characteristics. The findings of this study can be used as a guide for making decisions on groundwater abstraction and management.Item Assessing Environmental Impact and Socioeconomic Consequences of Oil and Gas Spillage on Soil in Warri, Southern Nigeria(European Centre for Research Training and Development UK, 2023) Shaibu, B.O.; Osisanya, W.O.; Amoyedo, A.A.; Akpeji, B.H.The Niger Delta terrain is often prone to environmental degradation resulting from oil and gas spillage. This research aims to assess the environmental impact of oil and gas spillage on the soil of Warri, Southern Nigeria, by utilizing physicochemical properties, statistical analysis, and socioeconomic information to evaluate the impact of heavy metals in the study area. A total of six (6) soil samples were collected and examined with the aid of an atomic absorption spectrometer (AAS) using a procedure that adheres to World Health Organization (WHO) standards. Concentration levels of Sodium (Na), Potassium (K), Calcium (Ca), Magnesium (Mg), Exchangeable Acidity (EA), Exchangeable Cation Exchange Capacity (ECEC), Total Petroleum Hydrocarbons (TPH), Zinc (Zn), Copper (Cu), Iron (Fe), Cadmium (Cd), and Lead (Pb) were analyzed and found to range from (21.1-74.98) ppm, (23.46-105.57) ppm, (1281442) ppm, (58.80-341.60) ppm, (0.25-13.50) ppm, (11.51-14.78) ppm, (11.30-226.34) mg/kg, (98.26 122.60) mg/kg, (10.10-18.43) mg/kg, (321.86-994.04) mg/kg, (0.26-0.50) mg/kg, (0.4-1.15) mg/kg, respectively. The research revealed that the soil pH ranged from highly acidic to slightly acidic, which can negatively affect nutrient availability and plant growth. The research also highlighted the detrimental impact of oil spillage on the health, livelihood, amenities, and socioeconomic state of affected communities. Agricultural produce, crop yield, and livestock production were negatively affected due to poor soil fertility and damage to water bodies. Basic amenities were polluted, leading to abandonment and contamination of drinking water. The social environment of these communities experienced setbacks in occupation, income, and education. The findings provide valuable insights into soil characteristics and contamination levels and also show that regular soil quality monitoring and assessment are essential to detect any degradation in soil quality in the examined area.Item Assessment of Aquifer-Protective Capacity of Orire Estate in Akure, Ondo State, Nigeria(University of Port Harcourt, 2024-10-31) Olatunji-Adeniyi, O.; Ayua, K.J.; Osisanya, W.O.The amount and thickness of clay layers and surrounding organic elements have a direct impact on how well an aquifer protects itself. Thus, the purpose of this work was to evaluate Orire Estate's ability to preserve the aquifer in Akure, Ondo State, Nigeria, using a geophysical survey that used the Vertical Electrical Sounding (VES) and Very Low Frequency (VLF) Electromagnetic Technique. Throughout the course of the survey, seven traverses of various lengths were established, and VLF-EM measurements were made every five meters along the four main profiles. Thirteen vertical electrical soundings were also performed, with electrode spacings varying from one to one hundred meters. Computer-assisted modeling and partial curve matching approaches were used in the interpretation of the data. Four subsurface geological units were identified by the analysis: topsoil, worn layer, fractured basement, and fresh basement. The topsoil layer, with a thickness ranging from 0.9 to 1.5 meters, exhibited resistivity values between 57.0 and 198.4 Ω-m. The worn layer varied in thickness from 2.6 to 17 meters, with resistivity values from 87.0 to 978.7 Ω-m. The fractured basement layer's thickness ranged from 7.8 to 23.7 meters, showing resistivity values between 311 and 3041.8 Ω-m, while the fresh basement layer demonstrated resistivity values ranging from 1423.1 to 3790.57 Ω-m with infinite thickness. The presence of zones with poor aquifer-protective capacity throughout the study area indicates a heightened vulnerability to contamination from leachates and other pollutants. The subsurface conditions suggest an abundance of unconsolidated sand with limited clay, which prolongs the residence time of percolating pollutants and diminishes the necessary impediment to fluid movement for effective filtration.Item Assessment of Aquifer-Protective Capacity of Orire Estate in Akure, Ondo State, Nigeria(African Journals OnLine (AJOL), 2024) Olatunji-Adeniyi, O.; Ayua, K.J.; Osisanya, O.W.The amount and thickness of clay layers and surrounding organic elements have a direct impact on how well an aquifer protects itself. Thus, the purpose of this work was to evaluate Orire Estate's ability to preserve the aquifer in Akure, Ondo State, Nigeria, using a geophysical survey that used the Vertical Electrical Sounding (VES) and Very Low Frequency (VLF) Electromagnetic Technique. Throughout the course of the survey, seven traverses of various lengths were established, and VLF-EM measurements were made every five meters along the four main profiles. Thirteen vertical electrical soundings were also performed, with electrode spacings varying from one to one hundred meters. Computer-assisted modeling and partial curve matching approaches were used in the interpretation of the data. Four subsurface geological units were identified by the analysis: topsoil, worn layer, fractured basement, and fresh basement. The topsoil layer, with a thickness ranging from 0.9 to 1.5 meters, exhibited resistivity values between 57.0 and 198.4 Ω-m. The worn layer varied in thickness from 2.6 to 17 meters, with resistivity values from 87.0 to 978.7 Ω-m. The fractured basement layer's thickness ranged from 7.8 to 23.7 meters, showing resistivity values between 311 and 3041.8 Ω-m, while the fresh basement layer demonstrated resistivity values ranging from 1423.1 to 3790.57 Ω-m with infinite thickness. The presence of zones with poor aquifer-protective capacity throughout the study area indicates a heightened vulnerability to contamination from leachates and other pollutants. The subsurface conditions suggest an abundance of unconsolidated sand with limited clay, which prolongs the residence time of percolating pollutants and diminishes the necessary impediment to fluid movement for effective filtration.Item Assessment of heavy metal pollution on groundwater quality in the Niger Delta Region of Nigeria(Springer Nature, 2023-11-21) Eyankware, M.O.; Akakuru, O.C.; Osisanya, W.O.; Umayah, S.O.; Ukor, K.P.Heavy metal (HM) pollution in groundwater poses a significant environmental threat to the Niger Delta region of Nigeria, principally because of the activities of oil companies within the locality. The current study considered it necessary to measure the HM level in the groundwater of this location. 18 groundwater samples were collected and tested for physical parameters (pH, EC, TDS), as well as heavy metals (Cr, Cu, Zn, Co, Fe, Mn, B, Ni, and Cd). Results from the principal component analysis (PCA) analysis reveal the influence of heavy metals on groundwater chemistry. The correlation matrix results showed that there exists a weak and positive correlation among elements, revealing that heavy metals in water with a low pH tend to be more toxic, as they become more soluble and bioavailable. HM pollution assessment results revealed that the values were considered low, with values ranging from 0 to 0.33 with an average value of 0.07. Metal pollution index (MPI) results showed that the groundwater sample was very pure. Nemerow Pollution Index (PNI) results revealed that the groundwater samples were heavily polluted. Results from the modified degree of contamination (MCd), showed that the majority of the samples had a very low degree of contamination. The pollution load index (PLI) results indicated that the entire samples were polluted. Quantification of contamination (QoC) results showed a geogenic impact on the samples. Based on the findings, monitoring groundwater quality and using appropriate treatment technologies to purify the water before consumption are recommendedItem Assessment of Subsurface Competency Using Geotechnical Method of a Proposed Structure F.C.T Nigeria(Bilingual Publishing Co., 2022-12-30) Osisanya, O.W.; Diyanuwa, A.B.; Korode, A.I.; Ibitoye, A.T.; Ajibade, F.Z.Structural failure has been recently happenings mostly in the commercially populated states along the coastal line in Nigeria. As a result, an open field at a chosen location in Abuja, Nigeria, was investigated. For the purpose of this study, test bores were drilled and Standard Penetration Tests (SPT) were conducted at every 1.5 m interval up to a maximum depth of 12.0 m with the bearing pressure ranging between 20 kN/m2 and 1000 kN/m2. 3 test bores were drilled within the plot location, and samples were obtained at the test bore’s locations for laboratory analysis. Findings revealed that subsurface lithology found at the site within the explored depths of 0.0 12.0 m is mostly silty sand, laterite, sandy clay, silty clay, clayey sand, and weathered rock. The findings from the sub-soils of the different places and their bearing pressures were computed with SPT N value. Building foundations may be rigid raft foundations at a depth of 2.0 meters below the present ground level, according to bearing capacity values that range from 20 kN/m2 to 60 kN/m2 at 1.5 to 3.0 meters. The recommended building foundations take into account the sub-soil’s characteristics at the drilling places at a depth of between 1.0 and 3.0 meters. The structure might also be supported by frictional piles buried 10 meters beneath the surface.Item Critical Evaluation of Crude Oil and Sediments from Selected Areas of the Niger Delta.(International Journal of Earth Sciences Knowledge and Applications, 2026-08-03) Onoriode, D.A.; Ibe, K. A.; Osisanya, W.O.; Saleh, A.S.Understanding the occurrence, composition, and distribution of aliphatic hydrocarbons (AHCs) is crucial for assessing anthropogenic contributions and identifying the sources of AHCs in the environment. Therefore, this study focused on analyzing the concentrations, distribution patterns, and compositional characteristics of AHCs present in crude oil and sediments from the Udu, Ethiope East, and Ughelli North Local Government Areas. A total of nine crude oil samples and ten sediment samples were gathered from the research area. The concentrations of AHCs in these samples were quantified using gas chromatography with a Flame Ionization Detector (GC-FID) following extraction with a hexane/dichloromethane mixture and subsequent purification using a silica gel/alumina packed column. Analysis of the molecular indices indicated that the AHCs present in the sediments originated from marine biogenic, terrestrial biogenic, and petrogenic sources, whereas the hydrocarbons in the crude oil were derived exclusively from marine and terrestrial biogenic sources.Item DELINEATION OF GROUNDWATER POTENTIAL USING ELECTRICAL RESISTIVITY IMAGING TECHNIQUES AT IBULE AKURE, SOUTHWESTERN NIGERIA(Zibeline International Publishing, 2024) Adeniyi, A.E.; Osisanya, W.O.; Eyankware, M.O.Population growth and heightened water demand in the study area, exacerbated by insufficient surface and groundwater resources, lead to severe water shortages, particularly during the dry season. In response, our study in Atibioke Street, Aule Road, Ibulesoro, Akure, Ondo State, employed Horizontal Profiling (HP) and Vertical Electrical Sounding (VES) with electrical resistivity methods. Conducted across three traverses at 5m intervals, with probing levels from 1 to 5, the Combined HP and VES generated 2-D pseudosections, highlighting features and conducive layers for groundwater accumulation. Using Schlumberger configuration with electrode spacings from 1 to 100 m, three Vertical Electrical Soundings classified subsurface layers into Topsoil, Weathered Layer, and Fresh Bedrock within the basement complex terrain. The study emphasized the significance of electrical resistivity in assessing groundwater potential, with recommendations highlighting the unsuitability of VES 1 and VES 2 for exploitation, while VES 3 exhibited favorable conditions. Overall groundwater potential was rated as medium, emphasizing the need for alternative water supply solutions. VES 3 was recommended for well drilling based on promising characteristics, concluding with a suggestion to use these findings as a reference for future geophysical investigations.