2.5D Crustal Models Derived from Analytical Polynomial Separation Technique and Spectral Analysis of Gravity Data with Their Probable Gold Mineralization Migrations (Batouri, SE-Cameroon)
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: Gwé-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,
Gwé, and Bélimban, in the south of Guedal-Bélimban 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.
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