To achieve the current study, geoelectrical surveys along six (06) profiles of 4 km long in a 100 m × 200 m grid defined according to the triangulation principle in the Ngoura area (Tindikala-Boutou villages) have been made through electrical sounding and profiling following Schlumberger array. The instrument is the resistivimeter Syscal Junior 48 (IRIS Instrument) which uses the electrical current. The data have been processed and modelled with Res2Dinv and Winsev softwares then interpolated with Surfer software. Electrical methods used are the Direct current (DC) and the Induced Polarization (IP). Interpretation and analyses of results from each investigation method highlight weak zones or conductive discontinuities and mineralized zones. Conductive zones have been identified as shear zones within granitic structures of the Precambrian basement, according to the geologic and tectonic background of the area. The structural trend of these shear zones is E-W. The mineralization within it is N-S and characterized by high values of chargeability, essentially in the eastern part of the area under study. This mineralization proves the presence of metalliferous or sulphide heaps disseminated in weathered quartz veins which cross shear zones. Also, the poor mineralization and conductive structures in shear zones characterize the groundwater zones. The intense activities of gold washers encountered in the area enable to link that mineralization to gold within quartz veins. The near surface gold mineralization is eluvial or alluvial, and in depth this mineralization is primary.

The DJADOM-ETA area is in south-eastern of Cameroon, within the Congo Craton (CC) formations and composed of gneiss and amphibolite, migmatites and intrusive rocks. Few geophysical studies have been carried out over surrounding areas, but no investigation on the study area. The existence of aeromagnetic data covering the study area has motivated the application of a multiscale approach for tectonic features identification. The aim of this work is to interpret Aeromagnetic Data for Geological and Structural Mappings in the southeastern Cameroon. The GIS and GEOSOFT v8.4 softwares are used to treat data of Compagnie Minière du Cameroun getting in February 2012. The Tilt Angle method is used to delineate geological structures and to estimate the depth. The Euler's Deconvolution method is used to estimate the specific depth of structural contacts. The presence of bifurcations, accompanied by virgations, leading to the occurrence of several faults. Principal lineaments are determined with the main direction being ESE-WNW and E-W for the minor lineaments. The study highlights two major faults: ESE-WNW and ENE-WSW, where the former dominates, what could be called the geological accident of ETA. The Euler's Correlation and Tilt derivative contact map shows that most of the faults are vertical contacts. The geometrical description of this structure suggests an open synclinal transposed on vertical foliations: the major fault at the DJADOM axis is quasi-parallel to the Northern limit of the CC and parallel to the Sanaga Fault (SF) and the Central Cameroon Shear Zone (CCSZ). The features show a base strongly affected by tectonic which characterizes the transition between the zone from the CC and the belt from folds of the Pan-African. Also, the presence of the network characterizes the subsurface undulation in this study area: the intrusion of sandstone ochre quartz and schist of the Bek complex, the dolerite of the doleritic complex, and the silver micaschiste and ore quartzite in the base complex. On the TMI anomalies map, several places show high susceptibility contrasts, which is an indication of strong magnetization. Geological indicators point to inferred magnetite, dolerite and ochre schist quartzite which have a strong magnetization in this zone. The presence of weakly magnetized anomalies would be due to the migmatites of the base complex series. This study improved the knowledge of the subsurface structure of this area. It highlighted two major and minor faults. TMI anomalies map, in several places shows high susceptibility contrasts, which is an indication of strong magnetization.

A geophysical survey was conducted in the Kelle-Bidjocka village, Messondo subdivision, in the Centre Region, Cameroon. The data acquisition was made by combining Schlumberger profiling and electrical soundings along six (06) profiles of 1500 m in length for a total of 64 geoelectrical stations' survey conducted through a variable mesh 100 m × 200 m, or 100 m × 300 m. The equipment used is the DC resistivimeter Syscal Junior 48 (Iris Instrument). Processing and modelling of field data are made by using the Res2Dinv, Qwseln and Surfer software. The investigation methods used are electrical resistivity (DC) and induced polarization (IP) methods. The analyses and interpretations have helped to highlight areas of weakness or conductive discontinuities (fractures, faults, shear zones, etc.) in Precambrian gneiss formations, sometimes undergoing weathering processes. They identify the weathering or mineralogical accumulation horizons, the most promising is a mineralization channel identified in the NE-SW direction. The highlighted mineralization is characterized by strong gradients of chargeability or polarization. Samples and other geological evidences observed in the area are used to associate the most polarizable structures with ferriferous formations. Weakly polarizable and particularly conductive backgrounds identified by the inverse pseudo-sections are thought to be sulphate minerals or groundwater targets for future hydrogeological studies.

Yaounde zone is originally characterized by the small number of aquifers and bad renewal capacity. Within the framework of the emergency program which aims at supplying the city with drinking water, seventeen Vertical Electrical Soundings (VES) were carried out using Schlumberger configuration in parts of Yaounde (latitude 3˚-5˚N and longitude 11˚-13˚E) to determine the nature and thickness of aquifer zone and necessary geoelectrical parameters. Four to five geoelectric layers were delineated from the survey area. The first layer is the topsoil and has resistivity values ranging from 13-216 Ω•m and thickness is between 0.1-6 m. The second layer made up of clay sand and laterite has resistivity values ranging between 23 and 923 Ω•m and thickness ranged from 1 and 40 m. The third and fourth geoelectric layers consisting of clay and gneiss/migmatite with thickness varying from 1.7-63.3 m correspond to an aquifer horizon. Resistivity values of the aquifer ranges from 4 to 9215 Ω•m. The study indicates that average depth of the aquifer is 20 m and average thickness of the aquifer is 55 m. Soundings curves suggest several four layered geoelectrical sections KH, KQ, HK type and some five layered sections of the HKH, KHK types. KH type is dominant and can be used as reference for future studies. The resistivity survey reveals that the parameters obtained through interpretation of VES curves corroborate the litho logs of boreholes from the area.

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