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International audience; Marine gateways play a critical role in the exchange of water, heat, salt and nutrients between oceans and seas. As a result, changes in gateway geometry can significantly alter both the pattern of global ocean circulation and associated heat transport and climate, as well as having a profound impact on local environmental conditions. Mediterranean–Atlantic marine corridors that pre-date the modern Gibraltar Strait, closed during the Late Miocene and are now exposed on land in northern Morocco and southern Spain. The restriction and closure of these Miocene connections resulted in extreme salinity fluctuations in the Mediterranean, leading to the precipitation of thick evaporites. This event is known as the Messinian Salinity Crisis (MSC). The evolution and closure of the Mediterranean–Atlantic gateways are a critical control on the MSC, but at present the location, geometry and age of these gateways are still highly controversial, as is the impact of changing Mediterranean outflow on Northern Hemisphere circulation. Here, we present a comprehensive overview of the evolution of the Late Miocene gateways and the nature of Mediterranean–Atlantic exchange as deduced from published studies focussed both on the sediments preserved within the fossil corridors and inferences that can be derived from data in the adjacent basins. We also consider the possible impact of evolving exchange on both the Mediterranean and global climate and highlight the main enduring challenges for reconstructing past Mediterranean–Atlantic exchange.

Regional observations suggest that the Central Anatolian plateau (central Turkey) has risen by > 1 km since the Tortonian (~ 8 Ma) while significant crustal shortening did not occur. This uplift was preceded by the onset of widespread volcanism (~ 14–9 Ma). The lithospheric context of these events is however unknown. For the Eastern Anatolian plateau, similar events have been attributed to the late-stage evolution of the northern Neotethys slab, resulting in delamination and slab breakoff. Recent tomographic results indicate that this slab extended beneath both below the Eastern and Central Anatolian plateau just prior to delamination. We propose a new lithospheric scenario for the regional evolution in the Aegean–Anatolian–Near East region that combines a recent compilation of surface geology data with the structure of the upper mantle. Following the Cretaceous–Eocene closure of the northern Neotethys, Africa–Eurasia convergence was accommodated by horizontal subduction at a trench that was located south of Anatolia. Like before the closure, the northern Neotethys slab continued to sink into the deeper mantle beneath the Izmir–Ankara–Erzincan suture. In the early Miocene (~ 20–15 Ma), the northern Neotethys slab started to retreat southward to the trench, resulting in delamination of the lithospheric mantle. The last part of this scenario is testable, whether delamination can explain the uplift of both the Central and Eastern Anatolian plateau. In the east, uplift due to collision of Arabia is included. We use a coupled thermal–flexural model of the lithosphere. The model results show that delamination can explain the average present-day long-wavelength topography of the Central Anatolian plateau. For the Eastern Anatolian plateau, delamination explains half the present-day elevation. We find that a single delamination event also accounts for the present-day surface heat flow and Curie-point depth in both plateaus. We therefore propose to refer to central and east Anatolia since the middle Miocene as “the Anatolian plateau”.