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Abstract Lately, Saudi Arabia has been developing its mineral exploration. However, comprehensive studies of the collected data are not accessible. Thus, the purpose of this research is to identify and map the hydrothermal alteration zones and structural lineaments that regulate the mineral occurrences in the Nuqrah region of the Kingdom of Saudi Arabia using remote sensing and aeromagnetic data. To achieve the desired goal of the study, ASTER remote sensing data were employed, and they were processed in several ways, including principal component analysis, band ratio, and false color composites to reveal the zones of alteration and structure lineaments. In addition, aeromagnetic data was employed to map the lineaments controlling the mineralization. These datasets were integrated using GIS tools to generate a new mineralization potential map of the Nuqrah area, which was classified into three classes: low, moderate, and high probability mineralization. The results showed thirteen intriguing anomalies (high potential mineralization) dispersed over the research area to be prospected. Additionally, techniques such as residual, regional, first vertical derivative, and tilt derivative were utilized to detect the potential mineral-related geologic structures. The results were validated by plotting known mineralization sites on our maps. Six significant faulting trends have been found, according to the lineament map and rose diagrams from remote sensing: NE–SW, WNW–ESE, N–S, ENE–WSW, NNE–SSW, NW–SE, and E–W. The research region is most affected by the NW–SE, ENE–WSW, E–W, and N–S trends, which are organized in decreasing order of magnitude, according to the rose diagram of the aeromagnetic maps. The applied approach can be employed to map potential mineral deposits in Saudi Arabia and similar zones around the globe.

Abstract This study presents a comprehensive analysis of mineralization exploration in the Egyptian Eastern Desert (ED), one of the most sought-after areas for those interested in mining industry, by integrating Landsat-9 images and geophysical magnetic data. Employing advanced techniques like Principal Component (PC) analysis, Minimum Noise Fraction (MNf) transform, and Band-Ratio (B-Ratio), the research focuses on mapping lithological units, hydrothermal alteration regions, and structural elements. Composite images derived from specific PC, and MNf bands, and B-Ratio exhibit superior lithological unit identification. The findings emphasize that there are significant variations in the types of rocks extend from the southern to the northern parts of the ED. Hydrothermal alteration mapping, guided by B-Ratio results, aids qualitative lithological discrimination. A novel false color composite image optimizes Landsat-9 B-Ratios, enhancing rock unit discrimination. Correlation analyses reveal associations between mineralization types and major lithological units, while exploration of the magnetic anomaly map highlights its role in correlating mineralization sites. Structural features, analyzed through Center for Exploration-Targeting Grid-Analysis (CET-GA) and Center for Exploration-Targeting Porphyry-Analysis (CET-GA) with Tilt Derivative of RTP (TDR) techniques, contribute to a robust association between regions with medium to high structural density and porphyry intrusions and mineralization. The study significantly supports the advanced exploration geoscience, providing insights into the geological structures and dynamics governing mineralization in the Egyptian ED.

Regional magnetic data in the southeastern segment of the Nigerian Niger Delta were evaluated with the aim of mapping deep-seated tectonic elements. Enhanced filtering operations and 3D forward modelling were applied on the magnetic data. These geologic features triggered the formation of rollover anticlines and faults that serve as structural traps in the study area. The filtered residual magnetic data revealed geologic structures characterized with NE - SW, N - S, and E - W orientations. The 3-D models detected the faulted crustal blocks, gradient zones, and intra-basement compositional magnetic variations. Furthermore, some prominent horst and graben structures as well as related normal faults characterized with distinct magnetic signatures were observed. Faults of base magnetic (of various compositions) were observed to be the fabricating mechanisms of the magnetic anomalies. Collectively, these structures influenced the patterns of magnetic anomalies with direct effects on the hydrocarbon trapping systems, as well as the pathways and accumulation zones for hydrothermal minerals. On the whole, the interpreted results revealed that the basement surface is rippling. Additionally, the depth result showed sedimentary thicknesses that ranged from 4–10 km. Again, the estimated crustal thickness varied from 14 to 19 km. This study has displayed the capabilities of the magnetic method in mapping the depth and configuration of basement rocks, which are crucial in controlling the formation of structural traps. Identifying these basement structures early helps in understanding the overall geological framework and potential hydrocarbon systems.

Abstract The Tilt-depth is a popular approach for determining depths of magnetic sources. As this method is based on the distance between contour levels of the tilt angle, it can lead to inaccurate depth estimates when the contour lines are distorted by the presence of noise. In this paper, we stabilize the Tilt-depth method based on the computation of stable vertical derivative obtained by the β-VDR method. The presented method is demonstrated on synthetic magnetic anomalies and real magnetic data from the Arabian Shield. The results obtained from the synthetic examples coincide well with the actual depths. These results proved the utility of the presented method in cases where the field is corrupted by noise. The real example shows that the presented method can provide valuable information on subsurface structures of the area where the Tilt-depth estimates are consistent with the result of the horizontal tilt angle. The findings show that the presented method is less sensitive to noise and can provide source edges and depths more clearly and with higher accuracy.

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

Abstract El-Alamein new city is regarded as one of the iconic cities of the Egyptian North Western Coast to be not only residential units but also summer resorts for tourist attractions. This study examines the efficiency of integrating geophysical methods for determining if clay lenses exist or seawater has intruded into shallow strata and for calculating the geotechnical parameters of near-surface layers for construction purposes. Nine electrical resistivity tomography (ERT) and shallow seismic refraction (SSR) profiles are conducted in this study. From ERT data, we observed the intrusion of seawater in layers at different depths. From SSR data, two layers are observed along profiles, while three layers are observed along the other profiles according to their velocities. Near-surface geotechnical parameters, that were calculated from SSR data, are integrated to evaluate our study area. Accordingly, it was considered a low-competent area and suitable for buildings with low heights, and the only difference is the intrusion of seawater, therefore, it is subdivided into 2 zones. In zone (A), the second layer is used as a foundation layer. Zone (B) is pretentious by the intrusion of seawater, and it is not suggested to construct any buildings or to improve the strength of concrete exposed to seawater in this zone to be suitable also for buildings with a low height.

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.

Abstract Understanding the dynamics of suturing and cratonisation and their implications are vital in estimating the link between the lithospheric mantle architecture and geothermal resources. We propose new interpretations of the Western Arabian Shield’s geodynamic styles and geothermal anomalies. In this work, features of the crust and mantle were interpreted from geophysical modeling to unravel the structural dynamics between the Arabian Shield and the Red Sea rift, as well as the influence of these mechanisms on the uplift of the Cenozoic basalts. Estimates of the lower crust thermal properties were also achieved. Spectral properties of the potential field were used to define the Curie isotherm, heat fluxes, geothermal gradients, radiogenic heat production, Moho configuration, and lithosphere-asthenosphere boundary. Results show new structural styles, micro-sutures, and significant thermal anomalies. The defined geothermal patterns were inferred to be due to localized initiation of tectonic and asthenospheric disequilibrium during the rifting episodes within the Red Sea. Also, magma mixing is initiated by the northward migration of magma from the Afar plume towards the Western Arabian Shield which drives local mantle melts beneath the western Arabia, thereby providing the pressure field required for magma ascent. The ascendant magma flow provides the heating source of geothermal reservoirs within the Western Arabian Shield. However, there are indications that during the episodes of rifting within the Red Sea and/or ancient Pan-African activities, the mixing process may have been altered resulting in crustal thinning and creating pathways of ascendant magma flow along the MMN volcanic line. Integrating geophysical and geothermal models indicated new zones of suturing and extensional tectonics between the amalgamated terranes. The geodynamic interpretation shows a new redistribution of terranes and continuous compressional and transtentional movements within the Arabian Shield.

Mapping the boundaries of subsurface geological structures constitutes a fundamental aspect of interpreting gravity data. Various methods relying on gravity derivatives have been introduced to delineate these boundaries. However, these approaches are not without their limitations, often leading to the generation of false edges or resulting in divergent outcomes. This article introduces a novel method that utilizes the power law approach and balanced total horizontal derivative for mapping gravity data edges. To assess the robustness of the proposed technique, we conducted tests on model examples and applied it to a real case study in northwest Vietnam. The results demonstrate that our method can accurately and clearly map edges in comparison to existing methodologies, while also preventing the generation of spurious edges in the output maps.

The Middle Benue Trough (MBT) in Northcentral Nigeria is a geologically significant area with vast mineral resource potential. Employing airborne magnetic and radiometric data, this study utilized the Centre for Exploration Targeting on enhanced total magnetic intensity data to reveal geologic structures, lithological units and mineralization zones. Lineaments predominantly trended in NE-SW direction, with noteworthy orientations in NNE-SSW and E-W. Radiometric anomalies correlated with distinct lithological units, pinpointing granitic gneiss, alluvium, shale, siltstone and sandstone. A magnetically concentrated and potassium-rich area indicated potential polymetallic-magnetic mineralization. The 2D model illustrated igneous intrusions influencing prevalent geologic structures, such as sediment baking and doming. Thorough analysis, including source parameter imaging, standard Euler deconvolution and 2D forward modelling, revealed sediment thicknesses below 1500 m. This research enhances understanding of the MBT’s geological features, offering valuable insights for mineral exploration and resource assessment in the region.

The Kontum massif plays a key role in the tectonic development of the central Vietnam terrane. However, most of the northern part of the Kontum massif is covered by sediments. In this paper, we determine for the first time the subsurface structures of the area using aeromagnetic data. We have evaluated the effectiveness of six enhancement techniques on a synthetic model before applying these techniques to real aeromagnetic data of the study area. The results obtained from these techniques show that the study area is dominated by E-W and ENE-WSW trending lineaments and the depths of most of these structures range from 50 to 550 m. The findings also show some probable granitic intrusions in the study area. Our study provides the first magnetic interpretation for a better understanding of the structural features of the northern Kontum massif.

Abstract Integration of potential field- and structural data make it possible to trace surface and subsurface large-scale geological structures of the Egyptian Nubian Shield (ENS). Obtained results indicate that the Northern Eastern Desert (NED) of the ENS is dominated by relatively younger (c. 580 Ma) E–W and NE–SW trending extensional structures that were controlled by the evolution and retreat of the Cadomian Arc. Density of such extensional structures increases with depth as displayed by the potential data. The prevailing structural trends in the Central Eastern Desert (CED) are NW–SE and WNW–ESE. Both trends are highly prompted by the timing of deformation upon the Najd Fault System, and are themselves dissected by a relatively younger NE–SW shearing trend. Lineament density in the CED is subordinate for both subsurface and near surface structures. The South Eastern Desert exhibits compressional and extrusion-related structures of two main prominent trends; WNW-to-NW (to the western part) and the N-, NNE- to NE (to the eastern part). The previously mentioned Neoproterozoic trends are remarkably influenced by the Oligocene–Miocene Red Sea-Gulf of Suez rift related fractures in the vicinity of the rift shoulder. The remarkable change in trends and densities of structural trends, especially in the NED, is interpreted in terms of concealing of the older structures by the younger extensional structures which in turns reflect an N-ward progressive deformation in the entire ENS. Gravity data are more appropriate in delineating the structural trends compared to the magnetic data which are largely affected by lithological variations and/or alteration zones and magnetic mineralogy.

The Abakaliki Anticlinorium and its adjoining areas were appraised with the object of delineating high geothermal potential zones. Spectral depth analysis involving an improved centroid technique was used to analyze high-quality magnetic data. The obtained geothermal parameters were gridded to map various geothermal features within the investigated area. The obtained results varied from 4.99–9.35 km, 2.31–6.15 km, 6.11–16.28 km, 35.63°C–94.93°C/km, and 89.07–237.32 mW/m2 for centroid depth, top depth, Curie point depth, geothermal gradient, and heat flow values, respectively. The delineated semioval structure in the central zone of the investigated region characterized by a shallow Curie point depth (< 8.5 km) correlates with the location of the high-heat flow (>191.0 mW/m2) and geothermal gradient (>74.0°C/km) region. The high geothermal potential of the region is triggered by the massive post-rift tectonic event of the Santonian period related to the Abakaliki Anticlinorium. Further geophysical exploration programs should be carried out before exploitation activities at anomalous geothermal regions.

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

Abstract This study delineated the Fe–Ti oxide deposit concurrencies on the layered mafic intrusion in Gabal Akab El-Negum (GAN), South Eastern Desert, Egypt, using aeromagnetic mapping and chemical analysis of the hosted mafic rocks and mineralogical studies. Aeromagnetic data was improved using the enhanced horizontal gradient amplitudeto detect the primary structures (edges/contacts/faults) that control the distribution of Fe–Ti ore deposit. GAN layered gabbros are differentiated into troctolite, olivine–, pyroxene–, and hornblende–gabbros. These mafic rocks primarily comprise plagioclase, olivine, pyroxene, and hornblende with Fe–Ti ores (magnetite and ilmenite). The significant variation in Mg# of clinopyroxene between 0.70 and 0.82 indicates the importance of fractional crystallization in developing layered mafic intrusion. Clinopyroxene and plagioclase thermometry yielded low temperatures similar to the fractionated primary basaltic magma. The pairs of magnetite–ilmenite minerals in gabbros provide equilibrium temperatures of 539.44–815.56, and high fO 2 , reflecting various cooling and subsolidus reequilibration phases of minerals. The enrichment of GAN gabbros in light rare–earth elements relative to heavy rare–earth elements indicates the interaction between the Fe–Ti rich mantle and the fractionated tholeiitic magmas in the back-arc setting, generating Fe–Ti oxide ores.

Abstract The debatable timing of India–Eurasia collision is based on geologic, stratigraphic, kinematic, and tectonic evidence. However, the collision event disturbed persistent processes, and the timing of disturbance in such processes could determine the onset of India–Eurasia collision precisely. We use the longevity of Southeast Indian Ridge (SEIR)—Kerguelen mantle plume (KMP) interaction cycles along the Ninetyeast ridge (NER) as a proxy to determine the commencement of India–Eurasia collision. The geochemical signature of the KMP tail along the NER is predominantly that of long-term coupling cycles, that was perturbed once by a short-term decoupling cycle. The long-term coupling cycles are mainly of enriched mid-ocean ridge basalts (E-MORBs). The short-term decoupling cycle is mostly derived from two distinct sources, MOR and plume separately, whereas the KMP is still being on-axis. The onset of India–Eurasia collision led to continental materials recycling into the mantle; hence the abrupt enrichment in incompatible elements at ca. 55 Ma, the MOR–plume on-axis decoupling, and the abrupt slowdown in the northward drift of the Indian plate was induced by the onset of India–Eurasia collision, thereafter MOR–plume recoupled.

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.

Litho-facies classification is an essential task in characterizing the complex reservoirs in petroleum exploration and subsequent field development. The lithofacies classification at borehole locations is detailed but lacks in providing larger coverage areas. The acquired 3D seismic data provides global coverage for studying the reservoir facies heterogeneities in the study area. This study applies six supervised machine learning techniques (Random Forest, Support Vector Machine, Artificial Neural Network, Adaptive Boosting, Xtreme Gradient Boosting, and Multilayer Perceptron) to 3D post-stack seismic data to accurately estimate different litho-facies in inter-well regions and compares their performance. Initially, the efficacy of the said models was critically examined via the confusion matrix (accuracy and misclass) and evaluation matrix (precision, recall, F1-score) on the test data. It was found that all the machine learning models performed best in classifying the shale facies (87%–94%) followed by the sand (65%–79%) and carbonate facies (60%–78%) in the Penobscot field, Scotian Basin. On an overall accuracy scale, we found the multilayer perceptron method the best-performing tool, whereas the adaptive boosting method was the least-performing tool in classifying all three litho-facies in the current analysis. While other methods also performed moderately good for the classification of all three litho-facies. The predicted litho-facies using seismic attributes matched well with the log data interpreted facies on the borehole locations. It indicates that the facies estimated in inter-well regions are accurate and reliable. Furthermore, we validated the estimated results with the other seismic attributes to ascertain the accuracy and reliability of the predicted litho-facies between the borehole locations. This study recommends machine learning applications for litho-facies classification to reduce the risk associated with reservoir characterization.

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 southwest part of Cameroon is composed of a range of geological structures and sedimentary basins, whose geological history dates from the Cretaceous, and their establishment would have originated from the opening of the South Atlantic. Among these structures, the most important is the Cameroon Volcanic Line, generally denoted CVL, followed by the southern part of the Central African Shear Zone (CASZ) called the Foumban Shear Zone (FSZ), the Ntem Complex, the Benue Trough, the northern margin of the Congo Craton, and many others. The major structures identified in this part are formed as a result of geodynamic activity between the Oligocene and the recent period, to which we can add the volcanism that exists along with the continental limit. The XGM201e_2159 model is used to highlight the geological structures of Southwestern Cameroon. First, we separated the regional and residual anomalies from Bouguer gravity data. Then, we used a combination of filters to enhance the signature of the residual anomalies in Southwest Cameroon. These filters identified various geological structures in the area. Finally, we applied the enhanced horizontal gradient amplitude (EHGA) and multi-scale horizontal derivative of the vertical derivative (MSHDVD) methods to reveal the geological contacts, allowing us to establish the corresponding structural map of the region. In addition, the results obtained in this study are the first to precisely define the circumferential demarcation of the continental and oceanic expansions of Mount Cameroon, while clearly illustrating the Bao, Bomana, Tiko, and Ekona faults that extend to the Bakassi Peninsula and the Douala outlet. Furthermore, they highlight the strike–slip faults in the summit vicinity. The structural map shows that most of the geological boundaries identified in the area are trending in the NE–SW, NNE–SSW, ENE–WSW, N–S, and NW–SE directions.

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 Manta-Ray Foraging Optimization has been adapted and implemented in computing model parameters from potential field anomalies originating from two-dimensional dipping faults. The inversion technique was originally demonstrated on magnetic anomalies from uncorrupted–then, corrupted synthetic datasets. Thereafter, it was experimented on profiles taken from mining fields in the United States, and Australia. The results obtained showed that the design procedure is admirably stable and flexible, especially when dealing with noisy data. It is also notably efficient in the quantitative resolution of geophysical inverse problems. The consistency in results obtained from analysis of deep-seated and shallow field examples, even when compared against background results, is also impressive. The new technique has also exhibited notable superiorities over other well-known and conventional techniques, especially on the grounds of convergence rate, cost, and quality of resolved anomaly parameters. Consequently, it is recommended for interpretation of other structures and modeling of other geophysical data like self-potential and resistivity data.

In this paper, a geophysical strategy based on the recently proposed Manta-Ray Foraging (MRF) Optimization algorithm is adapted and presented for the blind computation of depth/shape defining parameters from magnetic anomalies due to buried geo-bodies. The model parameters deciphered are the coefficient of amplitude (K), buried structure’s origin (x0), the depth (z), magnetization angle (α), and a shape factor (q). After detailed and piecewise design, the new inversion tool is originally trial-tested on anomaly data generated synthetically. The uncorrupted version of the test data is first analyzed, then - it is corrupted with noise varied at 5, 10, 15, and 20% corruption levels. Thereafter, it is experimented with magnetic profiles taken from exploration fields in the United States, Peru, and Egypt. From the evaluation of results obtained, the new procedure is observed as exhibiting outstanding stability and flexibility especially with noisy dataset and notable efficiency in the quantitative resolution of magnetic inversion problems. The results obtained for the field cases are also mostly consistent especially when compared with background results from similar studies conducted with other methods; further affirming the new tool as reliable for the geophysical investigation of buried minerals.

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.