Late Triassic tholeiitic magmatism in Western Sicily: a possible extension of the Central Atlantic Magmatic Province (CAMP) in the Central Mediterranean area?

Late Triassic basaltic rocks crop out in the Lercara area inWestern Sicily.Major and trace element composition, aswell as Sr–Nd isotopic ratios (87Sr/86Sri=0.7074−0.7076; εNdi=from−0.69 to −1.09) of the Lercara rocksshows many similarities with Large Ion Lithophile Elements (LILE)- and Light Rare Earth Elements (LREE)-richtholeiitic basalts of the Central Atlantic Magmatic Province (CAMP), that erupted during the Mesozoicfragmentation of the Pangea supercontinent and subsequent opening of the Central Atlantic Ocean. Thegeochemical features of the Lercara igneous rocks, together with the spatial distribution of the ~200 Ma oldCAMP rocks are unlikely to be associated with the arrival of a thermal anomaly in the form of a mantle plumeand are more compatible with adiabatic melting of passively upwelling sub-lithospheric mantle. The originalmelts variably interacted with lower crustal rocks before reaching the surface. AFC modeling suggests twodistinct differentiation paths including either simple mixing or assimilation-fractional crystallization processesinvolving lower crustal rocks. These interactions with continental crust indicate that an ocean basement mostprobably had not yet formed.