Etudes géostructurales et gà®tologiques du gisement de saphirine et kornerupine de Taivo-Tsiombe, domaine Androyen sud de Madagascar

Abstract

Tsiombe is located at the extremity South of Betroka shear zone. Many cartographic works have been realized in Southern part of Madagascar but our study area remains slightly studied. Some geological features with some structural lines had come out from former maps and sapphirine-kornerupine deposit is not mentioned. Of this fact, this study has been carried out to complete and to actualize lithological and structural information of the region. Besides petrography, this research has a particular attention on sapphirine-kornerupine deposit. Kinematics' fabrics linked to the analysis of the deformation identified on the deposit displays a thrust and shearing system, a structural mechanism, considered as responsible of the laying up of these deposits. The mineral indexes as the cordierite-garnet-sapphirine-kornerupine observed on our study area testify high grad metamorphism. Sapphirine-kornerupine rocks bearing of Taivo have been deposited in Tsiombe sinistral shear zone under a granulite facies.

Keywords: gitology, sapphirine, kornerupine, shear, thrust, Taivo, Tsiombe.

Auteur : Tsiorisoa Harempahasoavana E-mail : tsiorisoah@ gmail.com

Encadrant : Théodore Razakamanana Professeur titulaire de chaire de classe exceptionnelle, Université de Toliara