Granulites and associated dykes from the less well studied southern Ivrea-Verbano Zone (IVZ; around Ivrea town) are characterized by combining field, macro, micro and chemical (major and trace-element mineral composition) data in order to identify chemical and rheological variations in the lower crust that could be relevant for geodynamic implications. The Ivrea granulites are similar to those belonging to the Lower Mafic Complex of the central IVZ. The mafic lithologies experienced a stealth metasomatism (pargasitic amphibole and An-rich plagioclase) that occurred at suprasol-idus conditions by a pervasive reactive porous flow of mantle-derived orogenic (hydrous) basaltic melts infiltrated along relatively few, likely deformation-assisted, channels. Similar metasomatic melts are already reported in the central and northern IVZ, suggesting a massive regional hydration of the lowermost Southalpine mafic crust during the Early Mesozoic. The plastic behavior of the lowermost part of the crust, induced by its metasomatic hydration, could have promoted the Tri-assic extension of the Variscan crust and the beginning of the Alpine cycle.