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Geophysical surveying is crucial in the investigation of mineral resources in poorly exposed areas such as SE-Cameroon, a region known for its gold mineral potential. In this paper, gravity survey is carried out in the Batouri area, SE-Cameroon based on land gravity data from the Centre-south Cameroon. Therefore, an analytical polynomial separation program, based on least-square fitting of a third-degree polynomial surface to the Bouguer anomaly map, was used to separate the regional/residual components in gravity data. This technique permitted to better understand the disposition of the deep and near surface structures responsible of the observed anomalies in the Batouri area. Spectral analysis and 2.5D modelling of two profiles P1 (SW-NE) and P2 (N-S) selected from the residual anomaly map provided depths to basement. These depths constrain the gravity models along the profiles, indicating a variable thickness of the sedimentary infill with an approximate anomaly of -33 mGal. The 2.5D model of the basement shows a gravity body, with a signature suggesting two close and similar masses, which characterize the quartz-bearing formations associated here to granite and gneiss. Our work highlights a main heavy gravity: Gwe-Batouri anomaly, containing the major part of auriferous deposits located along the NE-SW direction. Further, three tectonic sub-basins bounded by normal faults have been highlighted at Guedal, Gwe, and Belimban, in the south of Guedal-Belimban depression. They are associated with the extension tectonics, more or less vertical tangential cuts and accidents that have affected the region. A correlation with previous results from tectonic, lithological and gold mineralization activities proves the relevance of the study and the need to intensify geophysical surveying in the area.

This study is based on the analysis and interpretation of aeromagnetic data using version 8.4 of the Geosoft Oasis Montaj Software, to map the subsurface or deep geological structures that affected the geological formations of the Ngaoundere area. The use of the standard aeromagnetic methods made it possible to draw up the maps of the residual magnetic field reduced to the equator (RTE), the horizontal gradient (HG), the analytical signal (AS) and that of the Euler solutions (ED) to find the main magnetic facies corresponding to these structures. The geological formations of the studied area thus appear to be intensely fractured by a NE-SW (N45°E) and ENE-WSW (N70°E) main orientation fault system, the depth of which has been estimated by combining the three-analytical methods HG, AS and ED. Advanced magmatic map analysis revealed dikes associated with vertical faults in the studied area. The development of an interpretative geological map taking into account the basic geology, the deep faults, the identified dikes and the mineralization index made it possible to extract a correlation between geological structures and mineralization of the studied area. The 2.5D modelling of two magnetic profiles plotted on the reduced residual map at the equator was performed to approximate the geometry and depth of the dikes sector, which are potential sources of mineralization here.

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.

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.

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 (