The Upper Curaca River Valley, characterized by an unremitting flat, low-relief terrain, is situated in a semi-arid tropical ecosystem known as the Caatinga, which has xerophytic vegetation and very shallow residual soils. The Caraiba deposit is a Paleoproterozoic sill-like intrusion consisting of magnetite-bearing hypersthenites, melanorites and norites mainly mineralized with disseminated-type Cu-ore (chalcopyrite and bornite) exploited since 1978.