Tectonics, gold structural control and lithostratigraphy of
Ferkessédougou metasedimentary basin, northern Côte d’Ivoire.
The study area is located in the Ferkessédougou belt in northern Côte
d’Ivoire, precisely 30 km east of the city of Ferkessédougou. The aim of
this study is to understand the tectonic which control gold
mineralization. A combination of remote analysis and field mapping work,
trenching, reverse circulation drilling hole, core drilling hole was
carried out and finally laboratory work (microscopy). Different
processing such as ACP, adaptive filters have been applied to Landsat 8
and Radarsat satellite images, in order to enhance information for
better lineament extraction. Also, different complementary techniques
(horizontal gradient, Euler deconvolution) were applied to the
areomagnetic map in order to highlight the different lineaments.
Four sets of lineaments have been producted by these images: N080-N100,
N030-050, N000-N020, N120-N135.The validation of these different linear
structures was made with field data. Thus, in the field, the
metasediments show a strong S1 schistosity, stirikes NNE, with and dips
towards the South-East, compatible with a D1 shortening episode. The
emplacement of leucogranitic batholith and tonalite induces deformation
(D2) which is shearing foliation S2. ). Later, diorite dykes induces the
S3 shearing foliation. The earliest form of gold mineralization is
located in quartz veins and fractures filled by sulphide ( pyrite). The
second form of gold mineralization is disseminated and hosted in the
sheared contacts betwween intrusive units with the metasediments.
Studies show that quartz veins control the highest gold grades in
tonalite unit. The mineralization of our study area is an IRGS type.
Keywords: Gold, mineralization, Pyrite, Ferkessedougou, Ivory Coast.