Geological Behavior (GBR)

This study presents a gravity-based investigation of sedimentary thickness and structural trends within the Sokoto Basin, Northwestern Nigeria, bounded by latitudes 13°00′N–13°30′N and longitudes 4°30′E–5°30′E. Bouguer anomaly values in the area range from 66.16 mGal to 93.08 mGal, with lower values associated with thick sedimentary cover and higher values indicating basement uplift or intrusions. The regional Bouguer anomaly map shows gravity values between 64.07 mGal and 93.77 mGal, highlighting a north–south gradient likely related to basement relief and tectonic influence. The residual Bouguer anomaly map isolates local features, with anomalies ranging from approximately -5.98 mGal to +5.65 mGal, corresponding to variations in sedimentary thickness and shallow intrusions. Spectral enhancement through upward continuation to 1 km suppressed shallow noise and emphasized deep-seated structures, while the First Vertical Derivative (FVD) map revealed tectonic trends in SW–NE, NW–SE, and N–S directions, indicating active faulting and lithologic boundaries. Structural analysis using CET lineament mapping confirmed regional fault alignments and deep-seated fractures acting as potential hydrocarbon migration pathways. Depth estimations using Source Parameter Imaging (SPI) indicated basement depths ranging from 0.931 km to 5.174 km. Power Spectral Analysis revealed two depth layers: a deeper layer (D1) with depths from 0.92 km to 5.02 km (average: 2.505 km), and a shallow layer (D2) with depths from 0.132 km to 1.178 km (average: 0.568 km). Euler Deconvolution with Structural Index (SI) = 1 yielded depths between -683 m and 5078 m, while SI = 2 gave a broader range from -832 m to 5474 m. The central-western zone near 13.2°N and 4.8°E was identified as a major sedimentary trough, marked by the deepest basement relief and highest sediment accumulation. These findings underscore the Sokoto Basin’s resource potential and demonstrate the utility of gravity methods in characterizing sedimentary basins.

This research is aimed at integrating Electrical Resistivity Tomography (ERT) and Seismic Refraction Tomography (SRT) methods to delineate potential aquifer zones in parts of MarabanRido, Kaduna, Northwest, Nigeria. The research area, located in Kaduna South, features a mix of deposits and basement rock formations, making it a challenging region for groundwater exploration. The ERT survey utilized the ABEM Terrameter SAS 4000 with multi-electrode configurations, while the SRT employed a 24-channel ABEM Terraloc Pro2 seismic acquisition system. Data from both methods were processed using advanced software—RES2DINV for ERT and ReflexW for SRT to generate 2D resistivity and velocity models. The topsoil layer exhibits a seismic velocity range of 650 to 800 m/s and a resistivity range of 50 – 400Ωm, overlying a weathered basement with seismic velocity range of 900 to 2000 m/s with resistivity values between 500 and 1000Ωm. A third layer with velocities from 920 to >1384 m/s corresponds to resistivity values of 2058–9486 Ωm, indicative of moderately to highly weathered granite transitioning into fresh basement rock. The average overburden thickness is approximately 8 m, with basement depths around 20 m. The depth ranges and structural patterns interpreted from the ERT data align strongly with the SRT results, confirming the reliability of the integrated geophysical approach. The strong correlation between wave velocity and resistivity distributions allowed for accurate identification of groundwater-bearing zones, particularly within fractured and weathered basement complexes. This integrated method proves to be a reliable tool for hydrogeological investigations in crystalline hard rock terrains, supporting its application in groundwater explanation.

Extinction events have played a pivotal role in shaping Earth’s biological and geological history, often leaving behind distinct markers in sedimentary and fossil records. These events, such as the Permian-Triassic and Cretaceous-Paleogene mass extinctions, are characterized by significant biotic turnover, often triggered by catastrophic phenomena like volcanic eruptions, asteroid impacts, or rapid climate changes. The unique geological and sedimentary framework of the Bengal Basin, Bangladesh, constitutes an important archive with which to reconstruct these events at the regional scale. The paper is about potential geological markers of global extinction events within Bangladesh, focusing aspects of sedimentary sequences, isotopic anomalies, and fossil assemblages. The study examines key formations such as the Gondwana sediments, Sylhet Limestone, and Quaternary deposits, analyzing their potential to preserve evidence of mass extinctions and associated environmental changes. By correlating these markers with global extinction timelines, the research aims to provide new insights into the regional impact of these events, while addressing challenges posed by rapid sedimentation, tectonic activity, and erosion. The findings are very important in showing the need for interdisciplinary approaches and advanced analytical techniques to unearth the geological legacy of extinction events in Bangladesh, offering a foundation for future research on Earth’s dynamic history.

This review presents a detailed examination of how the aeromagnetic method has been utilized in the Ilesha region of Southwestern Nigeria, which holds considerable geological and economic importance within the Ife-Ilesha Schist Belt. This technique has proved vital for understanding subsurface complexities, especially in mineral exploration such as gold, structural analysis, estimating depths, assessing groundwater potential, and identifying geohazards. Research shows prominent NE-SW structural trends associated with the Pan-African Orogeny, which are critical for the movement of fluids and the formation of minerals. The progression of studies reflects a shift from qualitative analysis to integrated multi-geophysical and remote sensing methods, improving accuracy in mapping and resource identification. The findings underscore the success of methods such as Euler deconvolution and analytical signal in revealing hidden structures and estimating the depths of magnetic sources, which can differ considerably across studies. Despite improvements, there are still gaps in comprehensive petrophysical analysis, understanding the evolution of structures over time, quantitative evaluations of groundwater, and studies on the environmental effects of mining. Future investigations should emphasize integrated 3D modeling, advanced inversion techniques, machine learning implementations, and systematic comparisons of methodologies to enhance geological models and promote sustainable resource management. This review is designed to be a foundational resource for comprehending the aeromagnetic method’s significance and implications in this geologically critical area.

The study presents a comprehensive analysis of well log data from the “XRO” oil field in the Central Swamp Depobelt of the Niger Delta, analyzing gamma ray, resistivity, neutron, density, and sonic logs to determine lithology and pore fluid content, computing geomechanical properties (bulk modulus, shear modulus, Young’s modulus, Poisson’s ratio, Vp/Vs ratio) and petrophysical parameters (porosity, permeability, water saturation, shale volume, bulk volume of water) using Interactive Petrophysics v4.6, identifying two distinct reservoir sands across five wells (RO5–RO9) with unique geomechanical and petrophysical characteristics, net pay thicknesses ranging from 234.51 ft to 993.57 ft, porosity and permeability in RO5’s sand units 1 and 2 at 0.386/0.338 and 91.36 mD/73.11 mD respectively, and high resistivity values indicating hydrocarbon presence except in RO8’s sand unit 1 where low resistivity suggests brine, thereby enhancing reservoir characterization and supporting efficient hydrocarbon development strategies.

East of the Matadi square degree, the transition from the metasedimentary protoliths of the Mayumbian Group to the clayey-sandy deposits of the Sansikwa Subgroup recalls a similar sedimentological history but distinct in their paleoenvironmental evolution, contrary to previous work establishing a discontinuity for these two lithostratigraphic units. Microscopic analysis coupled with field data interpretation revealed a depositional uniformity from the metasedimentary protoliths of the Mayumbian Group to the Sansikwa schists, a deformation synchronism and the absence of erosional unconformity at the base of the Sansikwa Subgroup, demonstrating a sedimentation singularity between the two units. This continuity places the Sansikwa Subgroup at the top of the Mayumbian Group and brings the Lower Diamictite to the base of the West Congolian Group.

Groundwater is a vital natural resource for sustaining human and ecosystem needs. The advent of Geographic Information Systems (GIS) has revolutionized groundwater research by providing a spatial framework for data integration, analysis, and visualization. This paper provides a comprehensive review of the applications of GIS in groundwater research. The review covers the use of GIS in groundwater exploration, monitoring, assessment, management, and modelling. Additionally, the paper highlights the advantages and limitations of using GIS in groundwater research and the future research directions.

The study investigated the importance and image behavior of integrated geophysical methods in mapping contaminant spread beneath the surface of a pollution site in Ogoniland, Southern Nigeria. Electrical Resistivity Tomography (ERT) and Ground Penetrating Radar (GPR) techniques constrained by Vertical Electrical Sounding (VES) data were employed to investigate the electrical properties of hydrocarbon contaminated soils that resulted from recent oil spills/leakage into the environment. Five (5) ERT and GPR lines and twenty-nine (29) VES data were acquired at the spill site. Basically, the electrical signatures from the resistivity measurements were able to image the subsurface layers and the associated contamination zone. GPR equally imaged the subsurface stratigraphy to a depth of 10.0 m beneath the surface. The interpretation of the five (5) ERT data showed consistency in the resistivity structure indicative of contaminant plumes with anomalously high electrical resistivity in the range of 1000-10,000 Ωm, a possible indication of hydrocarbon contamination. On the GPR radargram, regions of high electrical resistivities were in agreement with reduced GPR reflection behavior (shadow zones) and were limited to the near surface of the surveyed areas. Vertical electrical sounding delineated layers with high resistivity predominantly within the second and fourth geoelectric layers within pollution depths of 2.4 m and 11.9 m, respectively. As a result, the underground aquifer, relatively between 7.5 and 10.5 m, has been infiltrated by hydrocarbons. It can be seen from the study that geoelectric measurements on the surface can describe the distribution of hydrocarbon resistive zones as well as their conductive behavior that may be linked with the biodegradation of oil spills in the subsurface. Thus, the employment of these integrated methods for contaminant monitoring, hydrogeologic studies and remediation planning reduced the uncertainties, and they are of extensive relevance in mapping the geological behavior of polluted soils in contamination sites.

The purpose of this study was to use petrophysical parameters to estimate the Total Oil in Place (TOIP) and the area extent of hydrocarbon accumulations in reservoirs from an oilfield in the Niger Delta basin. During the project, each hydrocarbon bearing zone identified from two oilfield wells was measured for porosity, permeability, water saturation, reservoir thickness, and shale volume. Using the average results of petrophysical characteristics, twelve reservoir zones of interest (sand bodies) were identified, correlated throughout the field, and ranked. The area extents of the accumulations were then calculated using volumetric equations. It was determined that the recoverable oil reserves for Well-001 and Well-002 were 148.45MMBB and 145.91MMBB, respectively. The accumulation’s respective area extents in W-001 and W-002 were determined to be 0.974 acres and 2.92 acres. According to the obtained results, we assert that there is oil and gas that may be exploited in the field under study. We also assert that W-001 may be more productive than W-002 in terms of oil accumulation, while W-002 has greater gas accumulations than W-001. The study’s outcome is quite helpful since it gives field asset managers valuable insights they need to create their oilfield exploitation and recovery plans.

Mud logging is a vital process used to monitor, collect, process, analyze, and interpret drilling cuttings in relation to lag time, gas data, and drilling depth. This operation is conducted in a mobile laboratory, known as the mud logging unit, located at the well site during drilling. Equipped with specialized tools, the unit continuously detects gas in the drilling mud and intermittently analyzes gas in the cuttings. Often referred to as the “Eagle Eye” and the “General Secretary” of rig operations, mud logging plays a critical role in both real-time monitoring and comprehensive documentation. It provides uninterrupted surveillance of the drilling process, identifying changes in subsurface conditions, detecting potential hazards, and ensuring safety and efficiency. By observing and recording data such as gas shows, cuttings, and drilling parameters in real time, mud logging enables swift, informed decision-making and strategic adjustments to optimize performance and prevent costly incidents. Beyond its operational significance, mud logging enhances the understanding of subsurface conditions, contributing to improved reservoir characterization and guiding future exploration efforts. The data collected serves as a valuable archive for geological analysis, decision-making, and strategic planning. As such, mud logging is an indispensable component for the success and sustainability of drilling operations.