Nassara gold district is located at southwestern of Gaoua and precisely in the south part of Boromo greenstone belt. The combined study of the anisotropy of magnetic susceptibility, microstructures examination permitted us to identify four phases of deformation in relation to the orogeny eburnean. Field overlap relationships and microstructures show that D2 is a deformation with a strong flattening component. In the Nassara zone (carrier of the main mineralization), the deformation is mostly related to the NW-SE orientation D3, which has a shearing character. Finally, a S4 fracture or crenulation schistosity of NE-SW orientation in relation to D4 locally overprints the D3 factory. Thanks to the ASM we have arrived to trace the main structures and the secondary structures (Case of Nassara) of economic interest (Case of zone B). These last called satellite zone by the mining companies deserve to be explored in detail, because they have the same characteristics as the main structure of Nassara. Lineations are good kinematic indicators of the direction of creep of the materiel which has also channeled the hydrothermal fluids contemporary with the D3 deformation.

Burkina Faso, Boromo belt, Nassara shear zone, anisotropy of magnetic susceptibility (AMS), Satellite zone