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This study rigorously investigated the spatial analysis of leachate penetration at Lemna dumpsite, located in Calabar, Cross River State, Nigeria. Purposeful soil sampling, performed at specific intervals (5 m, 25 m, and 50 m) along the Electrical Resistivity profile line within the dumpsite, was augmented by water sample collection from five boreholes near Lemna dumpsite. Utilizing Electrical Resistivity Tomography (ERT) and Vertical Electric Sounding (VES) survey techniques, resistivity data were systematically gathered to comprehensively analyze the Leachate Penetration in the Lemna dumpsite. Laboratory analysis of soil and borehole water quality focused on Benzene, Toluene, Ethylbenzene, and Xylene (BTEX), with paired sample t-tests applied for statistical scrutiny. Analyzing the ERT and VES data employed sophisticated techniques embedded in Resistivity Two Dimension Invasion software and Advanced Geosciences Incorporation Earth Imager software. Substantial disparities (p

In this study, we have applied a stable downward continuation technique to magnetic anomalies from the global geomagnetic field model MAG2V3 to improve the resolution of magnetic data of the west central Arabian Shield, Saudi Arabia. Then, advanced interpretation methods such as the tilt angle of the horizontal gradient (TAHG), horizontal gradient of a modified tilt angle (HGSTDR), and enhanced horizontal gradient (EHGA) have been applied to downward continued magnetic dataset to highlight the main structural features in the region. The observed geologic structures from the magnetic analysis revealed NW-SE, NE-SW, and ENE-WSW orientations in the west central Arabian Shield. The depths of these structures were computed by the analytic signal (AS) technique and the obtained result shows depths varying from 1.2 to 9.2 km. This study provided a new map of the subsurface geological structures for a better understanding of the tectonic evolution of the west central Arabian Shield.

This study predicts sediment yield on various landuse surfaces within the Calabar River Catchment, Nigeria. Five experimental plots of 31 by 23 cm (representing urban, farm, grass, bare, and forest surfaces) were established on a convex slope series with a 20% gradient, oriented along the slope strike. Rainfall, morphological, and hydraulic stations were derived for each plot. Multiple regressions and Factor analysis were employed to analyse the collected data. The research identifies critical factors influencing sediment yield, such as rainfall amount, rainfall intensity, slope gradient, slope length, sand, silt, clay, vegetation cover, and infiltration capacity. The results (p

Recently, detecting the edges and geologic structures (deep and shallow) from potential field sources provides a fundamental tool for interpreting geological structures. Therefore, the high precision computation of the edges of potential sources is becoming an essential requirement for studying subsurface structures. In this study, nine common detectors like tilte angle (TA), Theta-map (TM), Horizontal tilt angle (TDX), hyperbolic tilt angle (HTA), Improved tilt angle (ITA), Tilt angle of the total horizontal gradient (TTHG), Tilt angle of the total gradient (TTG), improved Theta-map (ITM), and improved logistic (IL) were applied. These filters have been tested on theoretical models and real data (aeromagnetic) from the Wadi Umm Ghalqa area, South Eastern Desert of Egypt. The obtained results have shown that the improved logistic (IL) filter could detect edges more successfully than the other eight filters. The results of the IL method were used to generate new accurate structural maps for local and deep components of the investigated area. Moreover, surface structures obtained from remote sensing data were considered to control the interpretation of the mapped subsurface lineaments. Hence, the IL method can be utilized as a sharp tool for the high precision structural imaging of the potential data.

Dipping dykes are geologically important structures since they are very important structures for hydrogeological, geothermal and hydrocarbon research. Many methods have been introduced by researchers to interpret dykes from magnetic anomaly data, but each of these methods have limitations. Therefore, new techniques are constantly being developed to achieve better results. This study introduces a novel method based upon the Social Spider Optimization algorithm and tests the method using synthetic examples. The algorithm developed to decipher the source body properties, is presented in detail. The test data consists of synthetic anomalies corrupted by different levels of random noise and field anomalies from mining records in China and Turkey. The obtained results have showed that Social Spider Optimization is a reliable, stable and efficient tool for deciphering the physical properties of deep and shallow located dykes from magnetic data. In addition, the proposed method is recommended for inversion of other geophysics data such as self-potential and gravity data.

Some parts of the Middle Benue Trough (MBT) of Nigeria were evaluated with the aim of detecting prospective geothermal potential regions. Spectral depth analysis using a modified centroid procedure was applied to analyze high-resolution airborne magnetic data. The Curie point depth (CPD) within the study area is in the range of 6.0 and 16 km. It was observed that the Gboko Anticlines (GA) that are interrelated with the Santonian intrusions of Abakaliki Anticlinorium (AA) are characterized by thin CPD (6.0–8.0 km). The mapped geothermal anomalies within the GA with shallow CPD (74 °C/km) and heat flow (HF) (>155 mW/m2) values. The adjoining areas within the study area are defined by medium-deep CPD (8.0–16.0 km), medium–low GG (

Lineament detector and depth estimation method involving modern aeromagnetic data were employed to study parts of the Obudu Plateau and Lower Benue Trough (southeast Nigeria) with the aim of mapping thermo-tectonic geologic structures and estimating sediment thicknesses. In this investigation, the enhanced horizontal gradient amplitude (EHGA) (applied to both simulated and real data) and tilt depth approaches were operated. The simulated magnetic model employing the EHGA detector generated sharp and properly defined edges of magnetic bodies with the capacity to place peaks over source borders. The tilt depth technique showed thin and thick sedimentations that vary from ∼ 500 to ∼ 1000 m and ∼ 1500 to ∼ 2500 m, respectively. The observed geologic structures trend mainly in the NW and NE, as well as minor NS directions. These structures, generated by the Younger Mesozoic Granitic intrusions of calc alkaline ring complexes, and the Santonian Abakaliki Anticlinorium serve as paths for super enriched hydrothermal fluids migration and deposition. The applied methods can be used to decipher the geologic structures in alike zones around the world.

The hydro-lithostratigraphic units of the coastal area of Akwa Ibom State, Southern Nigeria were investigated involving electrical resistivity tomography (ERT) and Wenner array. This procedure and electrode configuration were adopted because of their wide range of sensitivity and inherent characteristics to geological materials. This study is aimed at defining the extent of saltwater invasions into the coastal and inland aquifers. The investigated area is divided into three zones A (≤0 40 km)) based on the distance from the survey locations to the shoreline. The saline aquifer of the control tomogram obtained at the shoreline (Ibeno Beach) is characterized by the electrical resistivity of 0.159–3.55 Ωm. Within Zone A, (Ukpenekang, Eastern Obolo, and Okoro Ette), the saline aquifer is defined by electrical resistivity values of 0.33–44.0 Ωm, 2.07–48.5 Ωm, and 8.0–60.0 Ωm respectively. In general, the Zone B saline aquifers are defined by electrical resistivity values of 0.602–64.5 Ωm. Furthermore, the third zone which is situated a distance >40 km from the shoreline, is described by relatively higher electrical resistivity values (38.9–3260 Ωm) and indicates a region free from saltwater incursions. Generally, the 2D ERT models showed that electrically resistivity values increase progressively inland.

Aeromagnetic data of the Agadir Melloul region (Morocco) has been previously interpreted to delineate structural lineaments using the tilt angle method. In this study, we show the limitations of the tilt angle method in extracting the boundaries of magnetic sources and reinterpret aeromagnetic data of the Agadir Melloul region using the improved logistic method. Initially, the tilt angle and improved logistic methods are tested on 3D synthetic magnetic models where the results obtained from the improved logistic method show improvements in the delineation of the actual edges of sources compared to the tilt angle method. Then, aeromagnetic data from the Agadir Melloul region has been enhanced by the improved logistic method for delineating structural features. The obtained result provides a new look at the structural lineaments of the study area.

For the first time, historical and recent records on fascioliasis in Egypt reveal the results of sympatric and allopatric fluke/snail interactions in the Manzala Lagoon area by exploring the susceptibility of the species Pseudosuccinea columella after exposure to the Fasciola hepatica isolates from Egypt. Many factors influence trace metal accumulation in Pseudosuccinea columella, including temperature and salinity. Meanwhile, other factors are important in decreasing the bioaccumulation of heavy metals as low pH, low temperature, and high organic content of the substrate. It is indicated, from this study, that the Fe and Cu contamination can be detected in Pseudosuccinea columella species. The abundance of these snails varied all over the seasons where the minimum value was recorded in summer while reaching the maximum in autumn. Moreover, the abundance increased with increasing rainfall and humidity during the winter season.

The LTHG and EHGA methods are enhancement versions of the gradient amplitude and can outline the edges of shallow and deep anomalous bodies simultaneously. Recently, these techniques have been used in approximating the edges of gravity and magnetic data. In this paper, we apply the LTHG and EHGA methods to the gravity dataset from the global gravity model WGM2012 to extract structural features of Northeastern Laos that appear as lineaments on transformed data maps. We also apply the tilt depth method to this dataset to estimate the depth of these lineaments. The findings showed that most of structures identified in Northeastern Laos are trending in the ENE-WSW, NE-SW, E-W, WNW-ESE and N-S directions with the depth ranging from 1.3 to 2.1 km.

The existing work deals with the structural analysis and detecting basement depth of G. Shilman area, South Eastern Desert (SED), Egypt. This work includes interpreting aeromagnetic data to map out structures within the study area and determine the depth of the magnetic basement which can be an aide to advance exploratory study. The first vertical derivative (1st VD) enhanced the short-wavelength and high-frequency features of the data. The analytic signal (AS) and horizontal gradient magnitude (HGM) maps well the structures of G. Shilman area. Statistical analysis of the delineated structures indicated that the NW, N_S, NNE and NE are the main structural trends controlling the study area. This suggests that the area was dominated by various stress regimes. The source parameter imaging (SPI) method which acts strongly at all magnetic latitudes was applied to the data to map the basement topography of G. Shilman area. The basement depths vary from about 0.1 km to about 1.5 km at the deepest part of the study area. The depth examination indicates that the recent deposits are not thick and reflect the shallow nature of the basement in G. Shilman area. The results of our study gives more accurate interpretation for the structural regime of the study area and can be applied for alike areas.

One major purpose of interpretation of magnetic data is to highlight edges of geology structures. In this paper, we applied the edge methods such as the enhancement of total gradient (ETG), normalized horizontal gradient (TDX), theta map (TM) and fast sigmoid (FSED) methods to delineate geological structures that appear as lineaments in transformed magnetic anomaly maps. Initially, these methods were estimated on a magnetic model for understanding their capability. Further, we applied these methods to real aeromagnetic data for determining lineaments of the Wadi Umm Dulfah area. Additionally, the depths of the magnetic sources in the area were also computed by the tilt depth method. The obtained results indicate the presence in the study area of three major lineament trends in NW–SE, N-S, and NE–SW directions, and most of the lineaments are in the depth range of 0.1 km to 1 km. These results bring a better understanding of the edge methods capability, as well as the geology structures of the Wadi Umm Dulfah area.

Determining the main structures that control sedimentary basins from magnetic and gravity data is an important step for hydrocarbon exploration. In this study, the structural features of the area, east of the Qattara Depression, was deduced utilizing the gravity and magnetic data. Regional-residual separation, lineament analysis, tilt derivative and spectral analysis techniques were utilized to realize this main goal. Fast Fourier transform (FFT) was used for regional and residual separation. The structural patterns of the area were outlined by lineament analysis. The bedrock depth was calculated by applying the spectral analysis method on twenty gravity and magnetic profiles. The coupled 2D and 2.5D modeling along the three gravity and magnetic profiles indicated that the region consists of horsts and grabens blocks, consisting of both acidic and basic rocks. Consequently, a structural map was made to identify the main basins and highs. Besides, it was observed that the thickness of the sedimentary cover varies between 2.5 and 5.5 km in the study area.

The subsurface structures can be extracted from geophysical studies. This study deals with the detection of lineaments from gravity data that are related to the boundaries of the subsurface structures. The methods used in this study such as the horizontal gradient, total gradient, enhanced horizontal gradient, and improved logistic are tested on synthetic model prior to application to real gravity data. The results indicate that the improved logistic filter can be an effective method for boundary detection of gravity data.

Identification of lateral boundaries for the subsurface structures is a popular topic in many applications of geoscience. For this purpose, many edge detection and enhancement methods have been introduced to determine the lineaments of subsurface structures. In this study, the improved parabola-based method has been applied to reveal the lineaments of subsurface structures of Nam Dinh province. The obtained results have shown that there are NW–SE trending structures in this region and most of the lineaments are in the depth range of 2 km to 8 km. These results provide a new perspective to help us better understand the structural framework and tectonic settings of the study area.

The study area has a complex geological structure and is studied for mapping the density interfaces using geophysical techniques. However, it has not been studied for mapping geological structures, such as contacts and faults that appear as lineaments in gravity data. In this study, the lineaments in the area have been delineated using Bouguer gravity anomaly data, though some modern processing methods, such as horizontal gradient amplitude (HGA), tilt angle of horizontal gradient amplitude (THGA), and enhancement of horizontal gradient amplitude (EHGA). Most of the identified lineaments are trending in the NW–SE direction and some WE-trending lineaments in the southeastern region. This study provides new information for a better understanding of the structural framework and tectonic setting of the Thua Thien Hue area.

The purpose of this study is to evaluate the effectiveness of the multi-electrode electrical resistivity methods and to better understand the aquifers in Laos. The improved multi-electrode electrical exploration (IMEE) methods and a SuperSting R8/IP system with 56 electrodes have been used to measure ten 2D-electrical resistivity and three induced polarization profiles, of maximum length 550 m, at four sites in the Phonhong and Thoulakhom districts of Vientiane province, Laos. The results revealed moderate resistivity regions (18–80 Ohm m) that correspond well with low chargeability values (0–21 ms) at depths from 22 to 100 m, indicating possible suitable layers of good quality groundwater. These results agree well with data from borehole 1 drilled in the Phonhong district, which indicated the location of the water table at 20 m depth where samples extracted from the drill cores have been identified as gravel and siltstone. Analyses of water samples from different existing and new wells in the survey areas, including Total dissolved solids (TDS), Electrical conductivity (EC) and pH, revealed mean values lower than the contamination thresholds, confirming that the water is suitable for drinking without causing health risk. The obtained results provide new information leading to a better understanding of the structural framework of the study area. These results also demonstrate that the IMEE methods may be an efficient tool for groundwater investigation in Vientiane Province, Laos, and these methods can be applied for groundwater exploration all over the world.

Amongst all the potential field methods, gravity data constitutes the frequently measured geophysical information for deep seated lithospheric structures. The present work aims to outline the structural pattern, the main basins of Sinai and the depths to both Conrad and Moho discontinuities (CMD) by utilizing the gravity data. Several basins were depicted based on high-pass filtered gravity map and much of them are in a close agreement with the former studies. Additionally, the dominant fault trends are NE, NW, EW and ENE. An empirical equation was applied to low-pass-filtered gravity data to estimate the depth of the CMD. However, the thickness of the sedimentary basins increases northwards, reaching approximately 8 km, the minimum depths of Conrad and Moho discontinuities were attained in the northern compartments to be about 18 and 31 km respectively. Meanwhile, far a way to the south, the maximum detectable depth of Conrad and Moho discontinuities are 21 and 37 km. Eventually, 2D gravity modeling was constructed and constrained by 15 drilled wells and the calculated depth of CMD to figure out the comprehensive lithospheric geometry beneath Sinai Peninsula.