Mantle control for a giant Neoproterozoic epithermal silver deposit: Imiter (Morocco)

Abstract

The giant epithermal Ag-Hg deposit of imiter (Morocco) is investigated to test a possible transfer of chalcophile elements from the mantle to superficial crustal levels during Pan-African times. The accretion of the Anti-Atlas belt at the West African continent is characterized by a four stage succession of events, that is, extension, subduction, moderate collision and extension. The strongest metalogenic activity which is dominated by base-and precious metal deposit formation, occurs during the late extensional stage at the Precambrian-Cambrian transition. In the Imiter Ag-Hg deposit, the origin of metals and ligands, deduced from S, fluid inclusions, He, and Re/Os data obtained on sulphide phases and gangue minerals, had a dominantly mantle source.