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Abstract: The Neogene basins of Southern Cyprus provide a good opportunity to improve the knowledge of the paleoenvironmental changes involved in the triggering of the Messinian evaporite deposition in the Mediterranean, and of their chronology, which is still questionable with regards to the parameters responsible for the triggering of the salinity crisis. It is still difficult to discriminate the individual effects of tectonics, climate, global sea-level changes. In Cyprus, considerable progress has been made on the events leading to the MSC, since the 70''s, in high-resolution microfossil biostratigraphy, astrochronology, cyclostratigraphy and magnetostratigraphy. A study of the Tochni section, in the Psematismemos Basin, correlated with previously studied sections in the western Polemi and Pissouri basins, allows these regional paleoenvironmental changes to be correlated with the major events identified in other Mediterranean basins. The depth of the basins, in which evaporites were deposited, and the increase of salinity leading to the formation of evaporites are better constrained and studies confirm that restriction proceeded by steps throughout the Mediterranean. The very short time involved in the triggering of the onset of evaporite deposition in Cyprus basins is marked by tectonic instability, and development of very shallow water fauna and microbial communities indicating the water level lowered significantly just before the beginning of the massive gypsum precipitation. Correlation with other peri-Mediterranean basins, where similar changes have been observed, confirms that the period preceding the deposition of evaporites may correspond to the final closure of connections between the Atlantic Ocean and the Mediterranean Basin, leading to a sea-level drop and important hydrologic changes. [Copyright &y& Elsevier]

Abstract: The Cenozoic Alpine orogeny caused the partition of Tethys into several basins. During the Late Neogene, the Mediterranean attained its final configuration, whereas, eastwards, the Paratethys, isolated from the World Ocean, disintegrated progressively into a series of smaller basins. As a result, an endemic fauna developed in these basins, mainly composed of brackish to freshwater faunas, indicating an environment affected by changes in water salinity. These small basins of the Paratethys were named “Sea-Lakes” by Andrusov [Andrusov, D., 1890. Les Dreissenidae fossiles et actuelles d''Eurasie. Geol. min. 25, 1–683 (in Russian)]. Subsequently this name was translated into “Lac-Mer” [Gignoux, M., 1936. Géologie stratigraphique, 2°édition, Masson, Paris]. In the Mediterranean isolated from the Atlantic at the end of the Miocene (Messinian), thick evaporites deposited, consisting of a marine Lower Evaporite unit and an Upper Evaporite unit, mainly of continental origin. Ruggieri [Ruggieri, G., 1962. La serie marine pliocenica e quaternaria della Val Marecchia. Atti Acad. Sci. Lett. Arti. Palermo, 19, 1–169.] used the term “Lago-Mare”, to characterize the brackish to fresh water environment which occurred within the Mediterranean at the end of the Messinian. During recent decades, numerous scientific investigations concerning the history of the Messinian within the Mediterranean were devoted to the understanding of conditions prevailing after the deposition of the marine evaporites. Brackish to freshwater faunas are found in several outcrops and boreholes in the Mediterranean, both in the uppermost beds of gypsum and inter-bedded within the clastic sediments of the Upper Evaporite Unit, immediately preceeding the flooding by the marine Pliocene waters. These faunas, because of their similarities with the fauna described in the Paratethys, were named “Paratethyan”, or “Caspi-brackish” fauna, this leading some authors to imply a migration of these fauna from Paratethys to the Mediterranean. However, others refute this hypothesis. New data induced some researchers to consider that exchanges existed between the Mediterranean and the Eastern Paratethys and also between the Mediterranean and the Atlantic Ocean at the Miocene–Pliocene transition. These investigations now take advantage of the accurate time scales established by authors (biostratigraphy, cyclostratigraphy, magnetostratigraphy), allowing good stratigraphic correlations between the Mediterranean and the Paratethys, and precisions on the geodynamic evolution of this area. Furthermore, sediments at the base of the Zanclean (MPl1), locally containing brackish to fresh water faunas conducted authors to attribute this formation to an infra- or pre-Pliocene and also to a Lago-Mare “event”. Thus, the “Lago-Mare” concept drifted from its original meaning, and is evolving because of progresses in the understanding of the Mediterranean geodynamics and the adjacent areas during the Miocene–Pliocene transition. [Copyright &y& Elsevier]