%0 Journal Article
%T Sesam, toward a Mature Magmatic Arc Sourced from Tholeiitic Volcanisms and Calc-Alkaline Volcanoplutonism within Kedougou-Kenieba Inlier, South-East Senegal/West Africa
%A Mame Codou Ndiaye
%A Mamadou Ndiaye
%A Papa Malick Ngom
%A Mababa Diagne
%A Andrea Moscariello
%A Antoine De Haller
%J Journal of Geoscience and Environment Protection
%P 331-386
%@ 2327-4344
%D 2025
%I Scientific Research Publishing
%R 10.4236/gep.2025.131018
%X The Paleoproterozoic terrains of Kedougou Inlier have an overall architecture formed of greenstones and sedimentary basins. Most of the work done on these Birimian formations has focused on either belts or basins, or even briefly on both, but more rarely on the transition zones between belts and Paleoproterozoic basins. Our study focuses on the lithostructural framework of the Mako-Diale transition zone located within the Kedougou-Kenieba Inlier. Its objective is to redefine the existing architecture. Geophysical, petrographic, structural and geochemical results from lithostructural domains allowed to building a new architecture based on three major lithostructural domains evolving into tectonomagmatic complexes associated with three shear zones corresponding to Western shear-contact (CiscoW) represented by Sabodala sinistral mylonitic shear (SSZ), to Median sinistral ductile then brittle shear-contact (CiscoM) and to Eastern dextral brittle-ductile shear-contact (CiscoE) corresponding to the Main transcurrent shear (MTZ). Tectonomagmatic complexes are represented by Maco oceanic crust, Sesam arc and Diale back-arc basin. The opening of Diale basin is related to CiscoM. Its closure set along the Faleme shear-contact (CiscoF) located beyong CiscoE. The tectonic evolution of the Eburnian orogeny within Kedougou-Kenieba inlier highlights four (4) deformations phases: CiscoW, CiscoM, CiscoE and CiscoF respectively running for D1, D2, D3 et D4. Such CiscoW along Sabodala, Sofia deposits and CiscoE along Massawa deposit, CiscoM and CiscoF stand as potential host structures for futures Kedougou inlier gold deposits. Furthermore, large plutonic masses within Mako-Diale transition zone belong all to three (3) distinct magmatic sources: Koulountou granodiorite, Koulountou and Tinkoto granites are sourced from high-K mafic rocks; Tiguida granite and Diabba granodiorite from low-K mafic rocks, while Dioudioukounkou granite belongs to tonalite source. The Sesam arc is located along the shear corridor defined between sinistral CiscoW and sinistral CiscoM. The main lithologies consist of volcanics (andesitic breccias or agglomerates, andesitic tuffs) reworked by Tiguida and Koulountou garnet granitoids. Magmatism is marked by MORBs tholeiites associated with arc tholeiites and calc-alkaline series: tholeiites3 with MORBs affinity, tholeiites4 with MORBs affinity, arc tholeiites and calc-alkaline2 series associated with island arc. Tholeiites are associated to metaluminous, syncollisional Koulountou garnet granite and peraluminous post-collisional Tiguida garnet
%K Magmatism
%K Tholeiitic
%K Calc-Alkaline
%K Garnet-Granite
%K Sesam-Arc
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=140274