On sheet 134 of the aeromagnetic map of Nigeria is a prominent northeast (NE) trending negative anomaly that extends for >20 km. This work reinterprets the anomaly using oasis montage™ 7.0 software, by inverse geological modelling of magnetic profiles. The aim of this work is to identify the Chibok magnetic anomaly as a plate tectonic feature, and as part of the West African Rift System. Three profiles were modelled across the residual magnetic anomaly, which yielded a depth range of 1 to 2 km. The result furnished a subsurface picture of ‘horst and graben’ which are characteristic of rifts. The sedimentary infill of the interpreted rift is considered to be sands/or sandstone due to the low magnetic anomaly. Sandstone has very low magnetic susceptibility [30 x106 emu (S.I.)] compared to granite and basalt. Geological data showed NW, NE, N-S, and E-W structural trends on the granitic basement. These manifest as faults, shear zones, joints and foliations. Emplacement of the Tertiary basalt in the NW of the area of study area showed planes of crustal weakness in the Precambrian basement. A palinspatic map of the area identified the pre-Tertiary geology. The sediment infill of the interpreted rift may serve as very rich aquifer for groundwater abstraction for irrigation in this semi-arid zone. The evidence of the plate tectonic nature of the interpreted rift indicated its alignment with offshore transform faults like Chain and Charcot as well as the Cameroun Volcanic Line.

A 3 Axis MCL6 Magnetometer was used to gather the magnetic data. The information was gathered from a 1 km by 500 m area along eight profile lines with a length of roughly 1000 m each. Each profile is spaced roughly 250m apart from the other. The magnetic investigation was created in a way that provided clear definition of the depth to phenomena in the region. Measurements of the magnetic strengths at discrete spots along traverses spaced consistently throughout the area of interest were required by the data collecting approach in order to sufficiently cover the segment utilized to ascertain the structure and deformation analysis of the study area. The geological conditions in the shallow subsurface provide the highest frequency events of interest, whereas magnetic property contrasts at or beneath the basement surface produce the lowest frequency occurrences. Significant lateral variations and contrasts in the shallow formations’ magnetic characteristics are produced either singly or as a result of a particular combination of faulting, deposition, and mineralization linked to displacement and deformation of the structural system.

In recent decades, urban sprawl has been viewed as one of the most pressing issues that cities over all the world in developing countries are batting with. It is often associated mostly with rural-urban migration and rising birth rates, where development is given precedence over urban planning. The study focuses on the urban sprawl of the greater Port Harcourt city. The greater Port Harcourt city is expanding at an unprecedented rate, with no adequate planning or statistical record. The study intends to address this issue by building models using remote sensing and geographic information system (GIS) tools in order to analyze urban sprawl in the Greater Port Harcourt city. To achieve this set of objectives, three sets of Landsat sensors, which were captured at different time intervals (1986, 2006, and 2021), were used to monitor urban sprawl in the study area. The Geographic Positioning System (GPS) was used during the field visit to collect the ground control points of some locations within the city. The National Population Commission (NPC) data was also employed to acquire the demographic statistics. The result of the study shows that the built-up area had expanded from 47.35 km2 (10.76%) in 1986 to 71.05 km2 (16.14%) in 2000 and to 284.68 km2 (64.68%) in 2021. This expansion in built-up area generates a decline in wetland, bare land, and forest land from 112.296 km2 (25.51%), 61.369 km2 (13.94%), and 160.152 km2 (36.39%) in 1986 to 72.468 km2 (16.47%), 86.486 km2 (19.65%), and 136.853 km2 (31.09%) in 2000, and to 42.810 km2 (9.73%), 10.858 km2 (13.94%), and 40.8384 km2 (9.28%) in 2021. The findings of the study are important because they give the government information on how quickly the study area is expanding, allowing it to adopt an appropriate planning strategy. In conclusion, the study demonstrate that remote sensing and GIS techniques can be utilized to successfully monitor the environment on a regular basis in order to investigate urban sprawl and inform better decision-making.

The hazards of being over-exposed to ionizing radiation at various mining sites are of great concern to environmental scientists. This study aims to measure the activity concentrations of 40K, 238U, and 232Th radionuclides at various mining sites of Paago, Iseyin local Government, Oyo state, Southwestern Nigeria using a well calibrated HPGe detector. Twenty (20) soil samples were obtained, analyzed, and compared with the WHO recommended standard. The results obtained indicate that 40K, 238U, and 232Th values ranging from 58.40 to 950.41Bqkg-1, 5.57 to 24.22Bqkg-1, and 4.1 to 25.93Bqkg-1. The gamma absorbed dose rate in the soil samples ranged from 6.85nGyh-1 to 45.73nGyh-1, with mean absorbed dose rate lower than the WHO recommended average value of 59nGh-1. The annual effective dose rates in the air varied from 14.26 to 19.74μ Svyr-1 with an average value of 17.99 μSvy-1, while the highest and lowest values of radium equivalent in the soil were 113.68Bqkg-1 and 21.62Bqkg-1. These findings shows that the external and internal hazard indices obtained were less than unity and the means activity concentration of the three radionuclides was lower than the world average recommended value indicating that the study areas pose no significant radiological threat to the populaces, and the crops are safe for consumption.

This study investigated the effect of channel planforms changes on potential river flooding in Kaduna state (River Kaduna as case study); with the aim to ascertain the effects of river channel planform on its potential flooding and put measures in place to advert the environmental menace. Topographic maps covering the entire course of the river and the characteristics of the river to be studied were obtained from the federal ministry of survey. The reliability of satellite images was verified by ground measurements using a 30m Surveyor’s tape on four bridges that cross River Kaduna. The measurements obtained were compared with correspondent measurements on the satellite image and found that the ground measurements and the measurements on both SPOT and Sentinel images were close. Three reaches (Meander 1, 2, 3; Straight reach 1, 2, 3 and Braided reach 1, 2, 3) were selected for this study. Variations measured along the river were changes in channel width, changes in sinuosity index, changes in braiding index channel lateral migration and changes in channel length from 1962 to 2017. The results showed a reduction in the channels width in all the reaches from average of 190m in 1962 to 74m in 2017; the sinuosity index was low in the duration considered (average of 1,15) while the braiding index value had a mean of 0.55. Channel migration also reduced from an average of 82m in 1962 to 53m in 2017 while the river reduced by 12% within this same period. The propensity of river flooding in the study area is high hence there is the need to carry out channel improvement, early warning system and desiltation of the river in order to eliminate the potential danger.

The sulphide ore mineralization occurrence in the area is structurally controlled. However, wrong structural delineation has led to some recorded mine failures and revenue loss faced by investors and government. Therefore, subsurface structural mapping is crucial for the successful and reliable delineation of sulphide ore enrichment zone within the area. To this effect ground magnetic method was used to appraise the structural elements associated with the sulphide mineralization in Ikenyi Izzi area, part of Southern Benue Trough. The total magnetic field intensity (TMI) was recorded, corrected, and separated into regional and residual magnetic fields. The TMI varies from 33259.7–33329.7nT with an average field value of 33299.4nT. Whereas residual susceptibility value ranges from -36.3–25.7nT with significant magnetic closures which correspond to the areas of low and high susceptibility values. Three dominant structural geometries was identified in the area; NE-SW>NW-SE>N-S with few E-W structures. The NE-SW and some N-S structures characterized areas of high magnetic anomaly closures and are associated with the regional trends of the igneous intrusive rocks, whereas NW-SE structures host the ore deposit (Trending ≥N300°) and dominantly associated with areas of low magnetic anomaly zones. The cross-cutting relationship of the NE-SW, N-S and NW-SE structures infers a close association of the intrusions and mineralization, which was validated by ground truthing. The residual susceptibility values of 1 to 10nT and ≥ 10nT were inferred as shale and intrusive rocks respectively. The implication of this study denotes that missing appropriate structural elements delineation could lead to abortive mines target.

The study aimed at predicting the porosity of reservoir sands in ‘Arike field’ Niger Delta, Nigeria by converting seismic trace of the interval of interest in the seismic survey into a porosity log to generate a porosity volume. Optimal number of relevant attributes were selected using multi-attribute analysis. The study discovered that three attributes (energy, velocity fan, and Q factor) were efficient. These attributes were then utilized to train a supervised neural network to establish the relationship between seismic response and porosity. The Opendtect software used, extracted all specified input attributes and target values over the specified range along the well tracks and randomly divided the data into a training and test set attribute. The study established the integration and correlation of energy attribute, velocity fan attribute, and Q factor as relevant seismic attributes for porosity estimation when little or no well log is available, hence giving a means of spatially extending well data.

In this study, it is demanded that a preparatory survey for an oil well location be carried out and the estimated number of dredged materials be calculated at various sections inside the perimeter of an oil mining lease (OML 38) located at Ovhor field, Niger Delta Region, Nigeria. Seven sub-sectional areas initially earmarked for dredging at predetermined depths were delineated for different purposes to accomplish the dredging task. The total sum of the seven sectional areas calculated was 89,321.31m2. Of the seven sub-sectional areas, the volume of dredged material was calculated for only five by multiplying the obtained two-dimensional areas by the designed depth. The two sub-sections exempted from dredging were because depths are appropriate at these locations. The total volume of dredged material, therefore, calculated was 56,630.73m3. Recording and monitoring of tidal observations and analysis complement bathymetry and dredging activities. Due to the rugged terrain, interpolation remains a viable option to predict spatial variability at unsampled dredged lines. To achieve this, different kriging methods were investigated before finally choosing the best. The model that made the most accurate predictions was “Indicator Kriging” with a mean error of 0.000364 and a root-mean-square-standardized error of 0.806. This result is geostatistically acceptable when predicting spatial variability at an un-sampled location. The indicator kriging approach was subsequently used to predict the spatial variability of the un-sampled locations encountered in the study area.

Six uphole seismic refraction profiles were acquired in Pindiga Field, Gombe in Nigeria, using seismic uphole refraction method. The aim of the study was parameterize the site of lithology, near-surface stratigraphy, and velocity for geotechnical and velocity regimes for seismic data processing. The data was recorded using Stratavisor Model NZXP Recorders, processed and interpreted using OMNI, Petrel, Landmark, UDISYS, SeisUp, WavePack, Excel softwares. The results of the interpreted data reveal three-layer cases having dominant geologic lithologic sequences of sandstone, clay and silt, and intercalation of laterite, ironstone, coal and gravels up to a depth of 65m. The sand is an admixture of the various sizes but demarcation is based on the size as define by Wentworth scale of classification. In the First Weathered Layer, the velocity varies between 363ms-1 and 453ms-1 with an average of 391ms-1. In the Second Weathered Layer, the velocity varies between 702ms-1 and 870ms-1 with an average of 834ms-1. For the Third Weathered Layer, the velocity varies between 1012ms-1 and 2104ms-1 with an average of 1182ms-1. In the Consolidated Layer, the velocity varies between 1012ms-1 and 2104ms-1 with an average of 1182ms-1. Velocity regime varies between 1235ms-1 and 2500ms-1 with an average of 1556ms-1. First Weathered Layer, the thickness varies between 2.6m and 4.7m with an average of 3.45m. Second Weathered Layer, the thickness varies between 0.9m and 41.5m with an average of 22.75m. Third Weathered Layer, the thickness varies between 12.5m and 45.9m with an average of 26.43m. The lithology, depth and velocity results of this work can be used to characterize a site, and also be applied in the processing of seismic reflection survey data.

A statistic is found useful in many applications of science where data and analysis are used for illustration and description for better understanding and justification of the data sets. Therefore in an attempt to achieve a better understanding and illustration of the dynamics of foundation integrity and vulnerability of failure, which often remain a major challenge to mankind, especially in Nigeria where foundation failures remain a major concern to both the Government and citizen. In this present study, a statistical approach was carried out on the Geophysical parameters in Issele-Mkitim area, South South Nigeria, to evaluate the dynamic factors that affect foundation integrity and vulnerability of subsurface lithologies. Very Low Frequency Electromagnetic (VLF-EM), Magnetic, and Electrical Resistivity Methods were used in this study. The Electrical Resistivity Method involved Lateral Horizontal Profiling (LRP) utilizing Wenner configuration. The three (3) methods correlated in terms of statistical prediction and understanding of the geologic dynamics natured associated with foundation failure and integrity. It was deduced that profiles one to six has high tendency of weak geological material which can easily lead to subsidence if any engineering construction is erected on it. However, proper consideration must be put in place to avoid future differential settlements. All the methods give useful information about the dynamics of the geological trends from the preliminary data analysis and interpretations, and a better understanding of the geodynamics nature of the soil as well as the region of a weak and competent zone in terms of engineering constructions.