We propose a revised age calibration of the onset of the Messinian salinity crisis (MSC) in the Mediterranean based on re-analysis of two “classical” sections: Perales (Sorbas basin, Spain) and Monticino (Vena del Gesso basin, Italy). The main novelties are recognition of an extra gypsum cycle in the transitional interval of the Perales section and the revision of the magnetostratigraphy in the Monticino section. We show that the first primary gypsum bed is located three precessional cycles above the C3r/C3An magnetic reversal, correlating to the summer insolation peak at 5.969 Ma; consequently we place the MSC onset in the preceding flexural point in the insolation curve at 5.971 Ma. Accordingly, we suggest that the MSC onset was preconditioned by the reduction of the hydrological exchanges with the Atlantic ocean and was finally triggered by glacial conditions in the northern hemisphere and by arid conditions in northern Africa

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The Messinian salinity crisis (MSC) is an extreme event in Earth history during which a\ud salt giant (>1 × 106 km3) accumulated on the Mediterranean seafloor within ~640 k.y. Erosional\ud unconformities extending from the continental margins into the deep basins are key features\ud for reconstructing the MSC; however, the nature of the erosional processes and their subaerial\ud versus subaqueous origin are highly controversial. This study focuses on the top erosion\ud surface (TES) in the deep Levant Basin, which is notably flat, truncating a basinward-tilted\ud Messinian evaporitic succession. Based on high-resolution seismic surveys and wireline logs,\ud we show that (1) the TES is actually an intra-Messinian truncation surface (IMTS) located\ud ~100 m below the Messinian-Zanclean boundary; (2) the topmost, post-truncation Messinian\ud unit is very different from the underlying salt deposits and consists mostly of shale, sand,\ud and anhydrite; and (3) the flat IMTS is a dissolution surface related to significant dilution\ud and stratification of the water column during the transition from stage 2 to stage 3 of the\ud MSC. Dissolution occurred upslope where salt rocks at the seabed were exposed to the upper\ud diluted brine, while downslope, submerged in the deeper halite-saturated layer, the salt rocks\ud were preserved. The model, which requires a stratified water column, is inconsistent with a\ud complete desiccation of the eastern Mediterranean Sea

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A revised stratigraphic framework for the Messinian succession of Cyprus is proposed demonstrating that the three-stage model for the Messinian salinity crisis recently established for the Western Mediterranean also applies to the Eastern Mediterranean, at least for its marginal basins. This analysis is based on a multidisciplinary study of the Messinian evaporites and associated deposits exposed in the Polemi, Pissouri, Maroni/Psematismenos and Mesaoria basins. Here, we document for the first time that the base of the unit usually referred to the 'Lower Evaporites' in Cyprus does not actually correspond to the onset of the Messinian salinity crisis. The basal surface of this unit rather corresponds to a regional-scale unconformity, locally associated with an angular discordance, and is related to the erosion and resedimentation of primary evaporites deposited during the first stage of the Messinian salinity crisis. This evidence suggests that the 'Lower Evaporites' of the southern basins of Cyprus actually belong to the second stage of the Messinian salinity crisis; they can be thus ascribed to the Resedimented Lower Gypsum unit that was deposited between 5.6 and 5.5 Ma and is possibly coeval to the halite deposited in the northern Mesaoria basin. Primary, in situ evaporites of the first stage of the Messinian salinity crisis were not preserved in Cyprus basins. Conversely, shallow-water primary evaporites deposited during the third stage of the Messinian salinity crisis are well preserved; these deposits can be regarded as the equivalent of the Upper Gypsum of Sicily. Our study documents that the Messinian stratigraphy shows many similarities between the Western and Eastern Mediterranean marginal basins, implying a common and likely coeval development of the Messinian salinity crisis. This could be reflected also in intermediate and deep-water basins; we infer that the Lower Evaporites seismic unit in the deep Eastern Mediterranean basins could well be mainly composed of clastic evaporites and that its base could correspond to the Messinian erosional surface