Controls on gold deposits in Hoggar, Tuareg Shield (Southern Algeria)

All the deposits are coeval and were formed at the end of the post-collisional stage (530-520 Ma). InHoggar, gold mineralization depend on a double control, first order giant sub-meridian shear zone control and the gold districts disposed in N40°-50°E corridors that may be interpreted as extensional. Indeed, the Hoggar gold province appears to have been controlled at all scales by the late transtensive reactivation of the Pan-African mega-shear zones, and by the correlative heat flux associated with the linear lithospheric delamination processes accompanying this reactivation; which are also responsible for the very lateHoggar magmatic events. At Amesmessa, gold deposition was promoted by the mixing of metamorphic fluids issued from the In Ouzzal Archean-Proterozoic basement with magmatic, basinal and meteoric-derived water. These deposits and occurrences contains variable minerals and trace elements in order of decreasing importance: Pb, Zn, Cu, Ag, Bi, W, Te,Co, Cr, Mo, Ni, Nb, Ta, U, Hf, REE, PGE.