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The integration of field and subsurface data permits a substantial revision of the sedimentary evolution of the Vena del Gesso basin, a thrust-top basin in the Northern Apennines where shallow-water primary gypsum deposits related to the Messinian salinity crisis were well developed and preserved. As inferred from lateral and vertical facies changes within the underlying deep-marine turbidites of the Marnoso-arenacea Formation, evaporite precipitation occurred in a basin bounded to the north and to the east by a thrust-related anticline actively growing since the late Tortonian. Both gypsum deposition and subsequent deformation were strongly controlled by evolving paleobathymetry driven by tectonics. Primary gypsum precipitated in a shallow, silled basin, while in the adjacent deeper and larger foredeep basin, organic-rich shales were deposited. Gypsum deposits underwent severe postdepositional deformation related to large-scale gravitational collapse, as a result of a regional uplift event, also coincident with the end of the evaporitic phase. Along the inner, shallower-dipping limb of the anticline bounding the basin, large-scale, poorly deformed gypsum slabs moved downslope along a detachment surface developed at the contact with the underlying euxinic shales, forming both extensional and compressional features and showing an overall southwestern vergence. The identification of a south-southwest-dipping paleosiope, here pointed out for the first time, suggests that the deformational features affecting the gypsum unit were probably driven by gravity and not by active thrusting, as thought up to now. The steeper frontal limb of the anticline promoted the transformation of gypsum slides into debris flows and turbidite currents that deposited their load in the adjacent deeper basin. This gravitational deformation was sealed by postevaporitic upper Messinian Lagomare deposits. The sedimentary history of the Vena del Gesso basin suggests that the Messinian salinity crisis in the Apennine foredeep, as well as in the Balearic, Tyrrhenian, Sicily, and Eastern Mediterranean Basins, was tightly linked to tectonic processes. The large-scale, postdepositional collapse of primary evaporitic deposits is a widespread feature in the Mediterranean basins, and it may have altered the original stratigraphic relationships in some places. This finding has potentially important implications for a correct paleoenvironmental reconstruction of the onset of the Messinian salinity crisis. Keywords: Messinian salinity crisis, Apennine foredeep, thrust-top basins, evaporites, slope instability, physical stratigraphy.

We present a new 87Sr/86Sr curve for the time interval between 6.5 and 5.5 Ma of the Ain El Beida section (AEB, Atlantic side of Morocco). The location and the precessional‐scale resolution of our curve allow to investigate the possible relationships between global paleoclimatic and palaeoceanographic trends and the high‐amplitude hydrological changes of the Mediterranean during the Messinian salinity crisis (MSC). The values, obtained from planktic foraminifers, plot in the upper portion of the global ocean curve and show long‐ (at eccentricity scale) and short‐term (precessional scale) oscillations; the latter are more evident during the maximum of eccentricity for both the 100 and 400 ka components, between 6.00 and 5.85 Ma. Negative 87Sr/86Sr anomalies are observed at insolation minima in phase with δ18O maxima, marking the glacial stages from TG34 to TG26. It is unclear whether these oscillations originated from local (river runoff) or global (glacial/interglacial) climatic forcing. Conversely, the evaporites of the coeval Primary Lower Gypsum (5.97–5.62 Ma) accumulated in the Mediterranean at insolation minima show positive anomalies at glacial stages TG32, 30, 28, and 26. Such an opposite trend is possibly related to the greater sensitivity of the Mediterranean Sea to river runoff during insolation maxima compared to the global ocean, as recorded at the Moroccan Atlantic margin. These observations and the deviation toward lower values of the Mediterranean Sr isotope curve starting at around 6.5 Ma, support the hypothesis of a progressive restriction of the Atlantic connections since the early Messinian, leading to the MSC. Key Points: A new planktic foraminifers‐based high‐resolution 87Sr/86Sr reference curve for the Atlantic (Ain El Beida section, Morocco) is providedLong‐ (at eccentricity scale) and short‐term (precessional scale) oscillations characterize the 87Sr/86Sr curveNegative 87Sr/86Sr anomalies are observed at insolation minima in phase with marine isotopic glacial stages from TG34 to TG26 [ABSTRACT FROM AUTHOR]

New palaeontologic, sedimentologic, and Sr isotope data allow to reconstruct a high‐resolution chronostratigraphic and palaeoenvironmental framework of the continental‐marine transition at the Miocene–Pliocene boundary in the Sorbas Basin (Betic Cordillera, South‐eastern Spain). The presence of Reticulofenestra zancleana, Ceratolithus acutus, and R. pseudoumbilicus in a marine horizon sharply overlying the continental deposits of the Zorreras Member indicates that the Messinian salinity crisis ended in the Sorbas Basin synchronously with the other Mediterranean basins at the base of the Zanclean, within the MNN12a biozone. Our results suggest that the Zanclean flooding turned the Sorbas Basin into a shallow bay with limited exchange with the main Mediterranean basin, probably through narrow seaways connecting also the Almeria, Nijar, and Vera basins. Our results do not confirm previous hypotheses envisaging an older age for the return to fully marine conditions in the Sorbas Basin and is in a good agreement with the reconstructions suggesting that the Zorreras Mb. continental deposits are the local time‐equivalent of the latest Messinian Lago‐Mare phase during the last stage of the salinity crisis. [ABSTRACT FROM AUTHOR]

The 87Sr/86Sr ratio is a proxy of the hydrologic structure of marginal basins characterized by the mixing between marine and continental waters. This reliable paleoceanographic and paleoclimatic tool is considered a key to the reconstruction of high‐amplitude hydrologic changes that governed the evolution of the Mediterranean region during the Messinian salinity crisis (MSC), when reduced connections with the global ocean resulted in the deposition of the most studied Earth's salt giant. Paleohydrological dynamics leading to the deposition of the Primary Lower Gypsum during the first stage of the MSC were revealed by the study of the 87Sr/86Sr composition of 114 samples from the Vena del Gesso basin (Northern Apennines, Italy). The analysis of seven high‐resolution 87Sr/86Sr profiles from individual gypsum beds suggests a climatic influence of precessional‐scale orbital parameters during evaporite deposition. The variations of Sr isotope ratios over time indicate that gypsum precipitation started from a seawater body dominated by continental contributions, followed by a relative increase of marine input. The overall results show a gradual upward detachment from the global ocean 87Sr/86Sr curve, with crucial steps corresponding to the most extreme eccentricity minima, suggesting an orbital influence on the hydrological balance of the basin. Given the sedimentological and geochemical analogies shared by the Mediterranean marginal basins that hosted the Primary Lower Gypsum deposition, the 87Sr/86Sr evolution of the Vena del Gesso basin may be considered as indicative of Mediterranean‐scale hydrologic dynamics, driven by gradual reduction of exchanges with the Atlantic and variable freshwater input. Key Points: High‐resolution Sr isotope data record orbitally forced climate control on basin hydrology at different time scales87Sr/86Sr profiles highlight recurrent precessional‐scale hydrological oscillationsThe stepwise divergence of the 87Sr/86Sr signal from the global ocean trend suggests gradual reduction of Mediterranean‐Atlantic exchanges [ABSTRACT FROM AUTHOR]

This integrated study (field observations, micropalaeontology, magnetostratigraphy, geochemistry, borehole data and seismic profiles) of the Messinian-Zanclean deposits on Zakynthos Island (Ionian Sea) focuses on the sedimentary succession recording the pre-evaporitic phase of the Messinian salinity crisis ( MSC) through the re-establishment of the marine conditions in a transitional area between the eastern and the western Mediterranean. Two intervals are distinguished through the palaeoenvironmental reconstruction of the pre-evaporitic Messinian in Kalamaki: (a) 6.45-6.122 Ma and (b) 6.122-5.97 Ma. Both the planktonic foraminifer and the fish assemblages indicate a cooling phase punctuated by hypersalinity episodes at around 6.05 Ma. Two evaporite units are recognized and associated with the tectonic evolution of the Kalamaki-Argassi area. The Primary Lower Gypsum ( PLG) unit was deposited during the first MSC stage (5.971-5.60 Ma) in late-Messinian marginal basins within the pre-Apulian foreland basin and in the wedge-top (<300 m) developed over the Ionian zone. During the second MSC stage (5.60-5.55 Ma), the PLG evaporites were deeply eroded in the forebulge-backbulge and the wedge-top areas, and supplied the foreland basin's depocentre with gypsum turbidites assigned to the Resedimented Lower Gypsum ( RLG) unit. In this study, we propose a simple model for the Neogene-Pliocene continental foreland-directed migration of the Hellenide thrusting, which explains the palaeogeography of the Zakynthos basin. The diapiric movements of the Ionian Triassic evaporites regulated the configuration and the overall subsidence of the foreland basin and, therefore, the MSC expression in this area. [ABSTRACT FROM AUTHOR]