L'unité ophiolitique du rio Magno en Corse alpine, élément des Ligurides de l'Apennin septentrional

Abstract

The Rio Magno unit (eastern Corsica) is represented by an Apenninic-type (Internal Ligurides) ophiolitic sequence: N-MORB basalts, Lower Cretaceous Palombini-bearing limestones, Middle Cretaceous flysch. In addition, it is unaffected by HP–LT alpine metamorphism. These peculiar features further support the hypothesis of close geodynamical relationships between the Corsican and Northern Apenninic ophiolites. We suggest that, in the Jurassic Piedmont-Ligurian oceanic basin, the Rio Magno and Internal Ligurides ophiolitic sequences represent a continuous, internal, oceanic palaeodomain. Afterwards, during Late Cretaceous–Late Eocene, they underwent a similar orogenic evolution, escaping from deep involvement during the subduction beneath the European continental margin.