The southern coast of the gulf of Corinth exhibits syn-rift deposits, giving insights into the first stages of continental extension as well as the geodynamic evolution of the surrounding Aegean region. The stratigraphy (relative position, 3D geometry, dating) of these deposits is still subject to controversies. The syn-rift evolution of the central part of the southern coast of the Corinth rift is revisited, based on new sedimentological and paleontological data. While ostracods analysis provides precise information about the paleoenvironments, recent advances in palynology supply a more accurate chronology.For the first time, we document marine evidences and Pleistocene evidences below the well-known giant Gilbert-type fan deltas of the Corinth rift. The syn-rift fill records a three-phase history: (1) the Lower Group corresponds to continental to lacustrine environments passing up progressively to brackish environments with occasionally marine incursions from before 1.8 Ma to some time after 1.5 Ma, (2) the Middle Group corresponds to giant alluvial fans and to Gilbert-type fan deltas prograding in an alternating marine and lacustrine environment from around 1.5 Ma to some time after 0.7 Ma, and (3) the Upper Group corresponds to slope deposits, Gilbert-type fan deltas and marine terraces indicating the emergence of syn-rift sediments along the southern coast from at least 0.4 Ma to the present day, with alternating marine and lacustrine deposition controlled by the position of the Mediterranean sea level relative to the Rion Strait sill. Age et évolution paléoenvironnementale du remplissage syn-rift de la marge sud du golfe de Corinthe (Grèce)Mots clés. -Sédimentologie, Palynologie, Ostracode, Pléistocène, Rift de Corinthe, GrèceRésumé. -Le remplissage sédimentaire qui affleure sur la marge sud du golfe de Corinthe a enregistré les premiers stades d'une extension continentale mais aussi des éléments de l'évolution géodynamique de la région égéenne. La stratigraphie (position relative, géométrie 3D, datation) de ces dépôts est toujours sujette à controverse. Une nouvelle étude sédimentologique et paléontologique permet de proposer un modèle d'âge plus précis à l'aide d'une étude palynologique et une reconstitution paléoenvironnementale des dépôts basées sur les faciès sédimentaires et les assemblages d'ostracodes. Ce travail présente pour la première fois des indices marins et des évidences d'âges pléistocènes sous les fameux Gilbert-type fan deltas du golfe de Corinthe. Le remplissage syn-rift enregistre trois grandes phases : (1) le Groupe inférieur (Lower Group) correspond à des environnements continentaux à lacustres qui évoluent progressivement vers des environnements saumâtres avec des incursions marines ponctuelles à partir d'au moins 1,8 Ma jusqu'à 1,5 Ma, (2) le Groupe intermédiaire (Middle Group) correspond à des cônes alluviaux géants et des Gilbert-type fan deltas progradants dans une étendue d'eau alternativement marine et lacustre de 1,5 Ma jusqu'à au moins 0,7 Ma, et (3) le Groupe supérieur (Upp...

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The Sorbas Basin is the land reference of the Messinian Salinity Crisis (MSC) that affected the Mediterranean Sea in the latest Miocene. Its stratigraphy has been re-visited using calcareous nannofossils and planktonic foraminifers, which provide a reliable biostratigraphic frame and lead to particularly specify the relationships between the Sorbas and Zorreras members with Yesares evaporites. The evaporites overlie a shallowing upward sequence ending with the deposition of the Reef Unit and Terminal Carbonate Complex (TCC) on the periphery of the basin. The reefal carbonates of the TCC are overlain by clastic deposits that are foreset beds of post-MSC Gilbert-type fan deltas developed on the northern edge of the basin. These sedimentary structures are separated from reefal carbonates and the Reef Unit by the Messinian Erosional Surface (MES). The various facies of the Sorbas Member have been correlated with the bottomset beds of the Gilbert-type fan deltas despite some differences in palaeobathymetry. In the southeastern periphery of the basin, the MES separates the Sorbas Member from the Yesares gypsums. In the central part of the basin, a hiatus characterizes the contact between these members. The Zorreras Member postdates the MSC and entirely belongs to Zanclean. Its white "Lago Mare" layers are lagoonal deposits, the fauna of which is confirmed to result from Mediterranean-Paratethys high sea-level exchange after the post-MSC marine reflooding of the Mediterranean Basin. This study allows to reassert the two-step scenario of the MSC (Clauzon et al., 1996) with the following events:-at 5.971-5.600 Ma, minor sea-level fall resulting in the desiccation of this peripheral basin with secondary fluctuations;-at 5.600-5.460 Ma, significant subaerial erosion (or lack of sedimentation) caused by the almost complete desiccation of the Mediterranean Sea;