All the geological constraints for an exhaustive reconstruction of the Triassic to Tertiary tectonic history of the southern Dinaric-Hellenic belt can be found in Albania and Greece. This article aims to schematically reconstruct this long tectonic evolution primarily based on a detailed analysis of the tectonic setting, the stratigraphy, the geochemistry, and the age of the ophiolites. In contrast to what was previously reported in the literature, we propose a new subdivision on a regional scale of the ophiolite complexes cropping out in Albania and Greece. This new subdivision includes six types of ophiolite occurrences, each corresponding to different tectonic units derived from a single obducted sheet. These units are represented by: (1) subophiolite me ´lange, (2) Triassic ocean-floor ophiolites, (3) metamorphic soles, (4) Jurassic fore-arc ophiolites, (5) Jurassic intra-oceanic-arc ophiolites, and (6) Jurassic backarc basin ophiolites. The overall features of these ophiolites are coherent with the existence of a single, though composite, oceanic basin located east of the Adria/Pelagonian continental margin. This oceanic basin was originated during the Middle Triassic and was subsequently (Early Jurassic) affected by an east-dipping intra-oceanic subduction. This subduction was responsible for the birth of intra-oceanic-arc and back-arc oceanic basins separated by a continental volcanic arc during the Early to Middle Jurassic. From the uppermost Middle Jurassic to the Early Cretaceous, an obduction developed, during which the ophiolites were thrust westwards firstly onto the neighboring oceanic lithosphere and then onto the Adria margin.

In the Northern Apennines, in contrast to the Western Alps and Alpine Corsica, upper structural levels of the Late Cretaceous-middle Eocene subduction complex are still preserved and well exposed. This subduction complex developed in the LigurePiemontese basin since the Late Cretaceous time as a consequence of convergence between the Eurasia and Adria plates. Representative successions of this ancient subduction complex are well preserved in the Ligurian units of the Northern Apennines, where turbidite and mass-gravity deposits showing pristine stratigraphic features are present. Three main domains, represented by different groups of tectonic units, can be identified, each delineating a different domain of the subduction zone. In this article, we first present a brief history of geological research in the Northern Apennines during the last half of the twentieth century and then a comprehensive picture of the stratigraphy and tectonics of the Ligurian units. A new interpretation of the related tectonostratigraphic units is proposed within the conceptual modern geodynamic framework of convergent margins.

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