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The Pan‐African mobile zone, situated at the margin of the Congo Craton in Cameroon, is characterized by a geological setting with polyphased tectonics, which can be summarised as the alternation of compression and extension events. The present study, conducted in a portion of the aforementioned zone, is aimed at investigating crustal structures using aeromagnetic data. To achieve this, a variety of advanced analysis and interpretation techniques were applied to reduce aeromagnetic data at the equator, including total horizontal derivative (THD), Centre for Exploration Targeting (CET), 3D Euler deconvolution (ED), spectral analysis, and 2D3/4 modeling. The results indicate that the study area can be divided into four magnetic units based on the magnetic properties (magnetic susceptibility, geometry, and depth) of the underlying rocks. The THD method reveals the presence of pseudocircular and linear structures, which are associated with mafic intrusions and faults, respectively. The structural trends of the lineament generated semiautomatically using the CET method suggest that the structures are oriented in order of priority: E‐W, WNW‐ESE, ENE‐WSW, and NE‐SW. These directions are probably related to the Pan‐African orogeny. According to the ED, the depths of these lineaments extend beyond 1250 m. A spectral analysis conducted on a profile intersecting some of the significant anomalies on the reduction to the equator (RTE) map indicates that the average depths of superficial and deep magnetic sources along this profile are approximately 0.5 and 6.5 km, respectively. The geological model obtained along this profile by direct 2D3/4 modeling indicates the presence of an ancient granitic basement, which is overlain by younger formations belonging to the Pan‐African. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate crustal structures from East Cameroon, using aeromagnetic data. The modeling of aeromagnetic data is conducted using the Oasis Montaj 8.0 software. The total magnetic intensity map reduced to the equator (RTE-TMI) shows important anomalies features, namely, the Northern East magnetic anomalies of high amplitude, the Southwest where very low values of the magnetic intensity were observed, and a corridor with negative values relatively high, separating the anomalies. The horizontal gradient map shows on the one hand brittle and folded structures carried out in the area of study and on the other hand various rectilinear, narrow, and short-wave anomalies that can be classified as a family of little faults. The maxima observed on the RTE-TMI maps are correlated to intrabasement contacts; and the map derived from Euler’s solutions permitted to evaluate the depth of the geological accidents observed from the other filters. This map also reveals new faults with a depth greater than 5000 m. The lineaments identified in the Southwestern part could be linked to the Pan-African orogeny and seem to correspond to deep-seated basement structures, which are referred to the tectonic boundary between Congo Craton and the Pan-African orogeny belt. A 23/4-D modeling confirmed the observations derived from the RTE-TMI and HGM maps analyses. It shows intrusive bodies composed of gneiss and porphyroid granite and some domes with their roof situated at various depths not exceeding 1800 m from the surface. The structural map of the study area shows the trending of the structural features observed, namely, NE-SW, NW-SE, ENE-WSW, and WNW-ESE, respectively, while the E-W and N-S are secondary orientation of the observed tectonic evidence. Moreover, circular anomalies observed over the area are assimilated to intrusions of high magnetic materials or to granitic domes.

New geological and structural facts have been identified under the auriferous lateritic cover in Garga Sarali, Ndokayo area. Data were collected using AMT receiver system with frequencies ranging from 20 Hz to 50000 Hz. It consists of 16 AMT stations along 03 profiles, over Pan-African formations of East Cameroon. The wide frequency range enabled us to probe deep into the subsurface to obtain necessary information. Using Imagem software, coherency of data has been evaluated and only the data with a coherency below or equal to 0.7 have been considered. Two programs were used to map the subsurface. The pseudosections were obtained using IPI2WIN-MT, while geoelectrical sections were obtained using Stratagem Resistivity Plotter. Analysis of the curves of dimensionality tests shows that there is not always a complete superposition between the two telluric directions, translating the fact that the variation of the resistivity is not 1D, but rather 2D or 3D. Major features of 2D resistivity model from the respective profiles were identified. These features include a set of lower resistive formations going from the surface to 1000 m depth, lying on a set of resistive formations that appears at the surface and below the lower resistive formations. However, a very conductive layer was observed in depth in the three profiles. These facts show that the study area is made up of mixture of both conductive and resistive materials, suggesting a prolongation of the overlap between the Congo Craton and the Pan-African in depth to the north and the location of the CC/Pan-African limit above 4°N parallel accordingly. Deeper electrical discontinuities, interpreted as faults following a NE-SW trend, were highlighted. All these new data suggest that the study area underwent an intense tectonic activity with ductile to brittle deformations due to the presence of the BOSZ.

Exploration and production of groundwater, a vital and precious resource, is a challenging task in hard rock, which exhibits inherent heterogeneity. A geophysical survey was conducted in Méiganga, Mbéré department, in the Adamawa region, Cameroon. High-resolution electrical resistivity tomography (ERT) and self-potential (SP) dataset were collected in a gneissic terrain to solve the groundwater problem as people are facing acute shortage of drinking water in the study area. The analysis and interpretations based on resistivity models revealed substantial resistivity contrast between the altered gneiss that might contain water and massive gneiss and delineated five deeper groundwater prospects zones located at Yelwa, Ngoa-Ekélé, Sabongari, Ngassiri, and Gbakoungué, respectively. Nevertheless shallow groundwater zones (

In the Pitoa-Figuil area (Northern Cameroon), an interpretation of aeromagnetic data was conducted. The aim of this investigation was first to emphasize lineaments hidden under geological formations and secondly to propose two 2.75D models of the subsurface structures. Different magnetic data processing techniques were used, notably horizontal gradient magnitude, analytic signal, and Euler deconvolution. These techniques in combination with the 2.75D modelling to the aeromagnetic anomaly reduced to the equator permit to understand the stratification of the deep and near surface structures, which are sources of the observed anomalies. We managed to put in evidence and characterize 18 faults and some intrusive bodies. According to Euler's solutions, anomaly sources go up to a depth of 5.3 km. [ABSTRACT FROM AUTHOR]

This study focuses on the mapping of lineaments using remote sensing techniques and Geographic Information Systems. The aim is to carry out a statistical analysis of the lineaments in order to better understand the organization of fracturing in the Batie district, and to identify areas of high fracturing density and their relationship with the hydrographic network. The methodology implemented to achieve these objectives is based on the processing and analysis of Landsat 9 Operational Land Imager/Thermal Infrared Sensor (OLI/TIRS) satellite imagery and Shuttle Radar Topography Mission (SRTM) data covering the study area. After essential pre-processing of data, the following processing techniques were applied: Principal Component Analysis, Sobel Directional Filter with a 3 × 3 matrix and shaded relief of SRTM data with a sun azimuth of 345°, altitude of 45 m and an elevation factor of 3, followed by manual lineament extraction. The results reveal a total of 176 lineaments, ranging in size from 0.002 to 2.461 km, with an average length of 840.66 km. The projection of these lineaments on a Rose diagram shows a predominance of the North East–South-West (NE-SW) direction, which is the direction of the major tectonic fractures that affect the basement of Central Africa. These lineaments are organized into networks and corridors that define large fracture zones or corridors that control the drainage of the study area. The zones with networks show medium and high densities. This fracturing density gives good aquifer and reservoir potential to the study area. [ABSTRACT FROM AUTHOR]