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The integration of geology, geophysics and remote sensing data was used to map the Sangmelima granite-greenstone belt terrain located in the South Cameroon. The region was not easily accessible, because of dense vegetation and thick lateritic overburden. Aeromagnetic data were help in mapping new possible small greenstone belts and structural features in this area. Many of the identified lineaments are interpreted to represent fracture/fault zones, some of strike-slip faults. The NE–SW, NW–SE, N–S and E–W are the main revealed from remote sensing processing; while the NE–SW, E–W to ESE–WNW, NW–SE and N–S are the dominant structural trends revealed from aeromagnetic data. We distinguish three deformation events within the Sangmelima area: D1 is recorded by a sub-vertical penetrative S1 foliation bearing steeply plunging stretching lineations. D2 overprints D1 structures with tight-to-isoclinal folds with associated foliation, N160°−175°E and N05°−25°E ductile shear zones, indicating ENE–WSW shortening. The D3 strike slip shearing is likely the result of the Eburnean deformation phase. The mafic dykes are striking NE–SW, N–S and NW–SE, and field evidence and airborne magnetic data suggest that some of them intrude preexisting structures. Many faults/fractures might have originated during previous deformation phases and they were only reactivated during the pan-African events. Keywords: Remote sensing, Aeromagnetic, Lineament, Structural, Archeaen, Sangmelima, Cameroon

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.

With the aim to produce a detailed structural map and then enhance the geological information of the south-western Cameroon, a field gravity study is carried out in the Kribi-Campo-Ma’an area (SW Cameroon). This study area is assumed to undergo pending active tectonics as witnessed by several earthquakes [1]. Besides, the area has been affected by some shears that gave rise to many major faults including the Kribi-Campo Fault (KCF). This N-S lineament is an active fault corresponding to the NW margin of the CC [2] [3] and related to the development of the Kribi-Campo basin. The gravity data analysis enables to highlight many deeply-seated structural features trending in the NE, NNE, N-S, NNW, NW and E-W directions in this region. The NW-SE trend is more strongly developed than the other identified trends and could have deeply affected the major NNE structure. The NNE-SSW to N-S fractures and faults which are local relays of the Kribi-Campo fault are related to the Kribi shear zone. The fairly good clustering observed on local maxima of the horizontal gradient magnitude enables to suggest that the contacts outlined have vertical to subvertical dips. However, a probable interpretation of these features is that they are vertical to subvertical faults which follow the aforementioned directions. The location of the study area in the gulf of Guinea suggests that it sustains tectonics related both to the equatorial and the south Atlantic oceans opening.