Age refinement and basin evolution of the North Rifian Corridor (Morocco): No evidence for a marine connection during the Messinian Salinity Crisis

The Gibraltar Corridor: Watergate of the Messinian Salinity Crisis

“…We conclude that all gateways through southern Spain and northern Morocco reflect an uplift trend starting as early as the late Tortonian and show no evidence for a marine MSC connection to the Atlantic (Capella et al, 2017b(Capella et al, , 2018Tulbure et al, 2017;Van der Schee et al, 2018). We thus corroborate the alternative hypothesis of a Messinian connection through the Gibraltar region and present a computational reconstruction on how the dimensions of this "Gibraltar Corridor" may have evolved throughout the Messinian.…”

“…The top parts of the marine successions may have been removed by erosion, but the observed high sedimentation rates in combination with the shallowing upward trend in the Tortonian suggests that marine sedimentation is likely to have ended in the earliest Messinian around 7.0 Ma (Tulbure et al, 2017). We conclude that a connection through the northern basins could have persisted only for a short time after the enhanced rates of uplift that started during the late Tortonian.…”

“…Most of the gateway sediments that are now exposed on land have been intensively 97 studied, but the timing of corridor closure is still subject to significant uncertainty (Benson et al, 98 1991;Martin and Braga, 1994;Krijgsman et al, 1999a;Martin et al, 2001;van Assen et al, 2006; 99 Achalhi et al, 2016;Capella et al, 2017a). It is very difficult to pinpoint the exact location or timing of closure from field data alone, because the area which first blocks the marine connection is, by default, the area that experiences the strongest uplift and erosion and the sedimentary succession preserved is therefore often incomplete (e.g., Tulbure et al, 2017). In case an erosional surface is observed, the youngest marine sediments below the unconformity are always older than the final closure age (e.g., Hüsing et al, 2010).…”

“…The closure age of the North Rifian Corridor is less well-constrained because the marinecontinental transition is commonly missing in most of the scattered outcrops (Achalhi et al, 2016;Tulbure et al, 2017). The open and relatively deep marine sediments deposited in the North Rifian Corridor are all late Tortonian in age >7.35 Ma (Tulbure et al, 2017). The assemblages of planktonic foraminifera and calcareous nannoplankton reveal that the Messinian is not reached.…”

“…5a). Slab retreat in the western Mediterranean subduction zone underneath the Gibraltar Arc came to a hold in the late Tortonian (Van Hinsbergen et al, 2014) after which tectonic uplift processes took over in the Betic (at ~7.8 Ma;Betzler et al, 2006;Krijgsman et al, 2006) and slightly later in the Rif orogeny (at ~7 Ma; Capella et al, 2017a;Tulbure et al, 2017). During the early Messinian, all the Betic connections and the North Rifian Corridor were closed by Africa-Iberia convergence processes (e.g., Spakman et al, 2018).…”