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The Lom volcano-sedimentary formation belongs to the Adamawa-Yadé (AYD) domain of the Pan-African fold belt in Cameroon. It is a geological formation presenting mineral deposits of economic potential such as gold and diamonds. The area is under small-scale and many artisanal gold mines. A geophysical study was carried out in the village Yassa, a locality situated within this geological formation, close to an artisanal mining excavation in order to define and propose a model of potential mineralized targets. The geophysical study involved the combination of electrical resistivity tomography (ERT), induced polarization (IP), and self-potential (SP) methods. The acquisition of data consisted of 15 electrical tomography lines in Schlumberger arrangement and a collection of SP data along these profiles in the absence of injected current. The anomalies of possible sulfide mineralization were found at a depth of about 10–25 m with a major NE–SW trend by applying the Euler deconvolution to the SP data. The ERT and IP data allow the production of the 2D inversion which is interpolated to obtain pseudo-models of the isosurface of potential mineralization. The correlation of geological information and the 3D isosurface pseudo-models indicates the characterization of zones with sulfides, with high chargeability values (≥ 30 mV/V). A body exhibiting this high chargeability correlating with a low resistivity (≤ 60 Ω m) is observed south of the study area. This body linked to a sulfurized zone presents its roof at an average depth of 13 m with a lateral extension in depth and a NE–SW orientation in agreement with the overall orientation of the area's major tectonic lines. Another polarizable body, located in the near surface to the north of the study prospect over an average depth of about 10 m, correlates with high resistivity (4500 Ω m), thus characterizing a probable zone of silicification. [ABSTRACT FROM AUTHOR]

Resistivity method using seventy-sixth (976) Schlumberger vertical electrical soundings along forty-one (41) profiles are conducted in the Batouri and Ngoura subdivisions, East region of Cameroon, to investigate the subsurface layering, mineral potential, and groundwater resource characteristics. Results of quantitative and qualitative interpretation of data using Koefoed computation method reveal two to five layers having geometrical and electrical characteristics of geological layer models: topsoil (0.5 m < e p < 3 m ; 600 < ρ < 3000 Ω. m), lateritic soils (3 < e p < 20 m ; 1000 < ρ < 4000 Ω. m); conductive layer (5 < e p < 110 m ; 100 < ρ < 1000 Ω. m); fractured/weathered granite (20 < e p < 60 m ; 1000 / 5000 < ρ < 3000 / 9000 Ω. m); clayey layer (5 < e p < 20 m ; 600 / 1500 < ρ < 2000 / 3500 (dry) Ω.m); and fresh granites (ρ > 4000 Ω. m). From the qualitative interpretation of VES curves, the subsurface layering is depicted by nine (09) types of sounding curves (G, H, A, QH, KH, HK, HA, HKH, and KHK) characterizing the vertical changes and the typology of sounding curves in the East Cameroon crystalline basements. The lithology of the subsurface is dominated (more than 80%) by geoelectrical and lithological 1D models derived by the H, QH, KH, HK, HA, HKH, and KHK curve types. These models are characterized by the presence of conductive layers and fractured/weathered granites derived from tectonic activities of the region. Also, the resistivity method (VES) applied in this study bring information about variation of the resistivity with depth, geological structures, fractures, and rupture zones in the underground until 120 m depth. These abovementioned information reveal proper hydrogeological and mining conditions for an efficient evaluation of the mineral potential and groundwater resources. [ABSTRACT FROM AUTHOR]