Introduction
The significant West Africa’s gold production hosted by Birimian’s rocks (Milesi et al., 1989). In addition, gold production in recent years located in the Paleoproterozoic domain is the strongest growth in the world (Masurel, 2015). Seventeen Birimian belt are distributed over two reference alignments, Tehini-Dimbokro in the East and Ferkessedougou - Soubré in the center have been identified in Côte d’Ivoire (Tagini, 1971; Yace, 2002). Our study area is located thirty (30) km eastern of the town of Ferkessedougou, in northern Côte d’Ivoire and situated in the belt of Ferkessédougou which is subject of exploration and artisanal mining. This belt has been identified as a gold region in the geostructural classification gold-bearing regions of Côte d’Ivoire (Sonnendrucker, 1969). This study will allow us to carry out the chronology of various deformations, as well as the model of gold mineralization in this area.
1. GEOLOGICAL CONTEXT
Ivory Coast is located in the southern part of the West African craton, precisely on the Man Ridge (Bessoles, 1977). It comprises two large unevenly distributed geological units which are, on the one hand, a narrow coastal sedimentary basin bordering the Gulf of Guinea in the south of the country and, on the other hand, a crystalline basement of Precambrian age which covers 97.5% of the national territory. The Pre-Ecambrian basement of Côte d’Ivoire is subdivided into two major domains depending on the age of the formations encountered, which are: (i) the Archean domain formed of crystalline and crystallophyllian rocks and (ii) the Paleoproterozoic domain formed of rocks crystalline and meta - volcano -sedimentary (Figure 1) (Bessoles, 1977). These two domains of unequal areas are separated by the Sassandra fault with sinistral movement oriented North-South. The Paleoproterozoic domain in which our study area is located was structured by the Eburnean megacycle. The formations of this domain in Côte d’Ivoire are volcano-sedimentary belt generally oriented NNE-SSW (Tagini, 1971; Daouda, 1998). On a regional scale, the study area is composed from west to east: of a biotite granite, metasediments namely: sandstones and argillites and finally a granodiorite to the west. The study area is composed from west to east: of a granite, volcanosediments and the sequence: argillites, pelites and shale (Figure 2) (WAXI, 2018). This granite located to the west of the study area is a vast and very extensive pluri-plutonic batholith (more than 500 km in length), it is an assembly of small two-mica plutons relatively similar in shape to laccoliths (Ouattara, 1998).