TITLE:
Petrological and Structural Approach to Understanding the Mechanism of Formation and Development of Paleoproterozoic Calc-Alkaline Volcanic Rocks of West Africa’s Craton: An Example of the Mako and Foulde Groups (Kedougou Inlier in Western Senegal)
AUTHORS:
Adrien Gozo, Mahamadane Diène, Dinna Pathé Diallo, Edmond Dioh, Mamadou Gueye, Papa Moussa Ndiaye
KEYWORDS:
Volcanism, Calc-Alkaline, Kedougou-Kenieba Inlier, Tectonic Stress, Transpressive Tectonics
JOURNAL NAME:
International Journal of Geosciences,
Vol.6 No.7,
July
22,
2015
ABSTRACT: The calc-alkaline volcanic
formations in the western part of the Kedougou-Kenieba inlier crop out in three
complexes: the Foulde in the North and the areas of Mako and Baniomba in the
South. These complexes which either combine with the tholeiites or cut across
the sedimentary formations are composed of thin veins and massive lava flows.
They have many petrographic similarities and show chemical characteristics that
resemble those of island-arc rocks. At the tectonic level, the D1 deformation
phase preceding the formation of the basins and the transpressive tectonics
including an oblique convergence may account for the structural evolution of
the Mako volcanic belt. Its occurrence in different basins may be evidenced by
the composition of some lithophilic components like the Sr, Ba, U, Rb and the
composition of clinopyroxenes enriched in TiO2, FeO, Na2O
in the Foulde calc-alkaline volcanic rocks that developed in a sedimentary
environment.