The Messinian sea-level fall in the western Black Sea: small or large? Insights from offshore Romania

Abstract

The Messinian sea-level fall in the western Black Sea is poorly understood and often debated.We provide evidence for the sea-level fall, offshore Romania. There, the Messinian sedimentation is closely related to the gravitational collapse of the basin margin above the Maykop shales. This thin-skinned system controlled the Messinian lowstand depocentres.We estimated about 500–600 m of sea-level drop based on the erosional valleys cut into the formed lower Pontian slope and the Messinian erosional surface (MES). The Messinian lowstand sediments are delimited by the basal erosional surface (BES) formed at the onset of the sea-level fall and by the MES related to transgressive wave erosion during the initial slow rise in sea level. Subsequent rapid sea-level rise drowned the remaining erosional topography on the lower Pontian palaeo-shelf. Similar features have been described in the Mediterranean Basin.