Hypersalinity accompanies tectonic restriction in the eastern Mediterranean prior to the Messinian Salinity Crisis

Author(s): George Kontakiotis, Geanina A. Butiseacă, Assimina Antonarakou, Konstantina Agiadi, Stergios D. Zarkogiannis, Emilija Krsnik, Evangelia Besiou, Willem Jan Zachariasse, Lucas Lourens, Danae Thivaiou, Efterpi Koskeridou, Pierre Moissette, Andreas Mulch, Vasileios Karakitsios, Iuliana Vasiliev
Abstract: This study describes the hydroclimate evolution of the eastern Mediterranean Basin during the early Messinian (7.2 to 6.5 Ma) time-interval based on analysis of a succession at Agios Myron (Crete, Greece), prior to the onset of the Messinian Salinity Crisis (5.96–5.33 Ma). Specifically, we report sea surface temperature and salinity reconstructions based on a combined analysis of biomarkers and oxygen isotopes of planktonic foraminifera. Data reveal that a negative water budget and strong hydrologic and climate variability characterized the eastern Mediterranean Basin at this time, and we identify three distinct phases. In Phase 1 (7.2–6.9 Ma), a shift to more positive oxygen isotope values in planktonic foraminifera at ~7.2 Ma is attributed to progressive gateway restriction of Mediterranean–Atlantic corridors and subsequent cooling until 6.9 Ma. In Phase 2 (6.9–6.7 Ma), distinct warm and hypersaline events (at 6.9–6.82 and 6.72 Ma) resulted in stressed marine microfauna during periods of strong evaporation. An important step-change in the Mediterranean restriction at 6.72 Ma may have resulted from shallowing of the Mediterranean gateways and reduced Mediterranean marine outflow. During Phase 3 (6.7–6.5 Ma) this gateway shallowing reduced the oceanic input into the Mediterranean Basin causing significant hydrological changes, reflected in a wide range of temperature and salinity fluctuations accompanied by enhanced water-column stratification. The data presented here counterbalance the general lack of quantitative temperature and especially salinity estimates available for the Mediterranean Messinian, time interval where we still highly rely on modelling for such evaluations. This study highlights the severity of preconditioning stages leading to the Messinian Salinity Crisis in the Mediterranean and sets values for extreme salinity conditions that could still host marine life.
Organisation(s): Department of Palaeontology
External organisation(s): National & Kapodistrian University of Athens, Senckenberg Biodiversity and Climate Research Centre, Johann Wolfgang Goethe-Universität Frankfurt am Main, University of Oxford, Utrecht University, Museum national d'Histoire Naturelle
Journal: Palaeogeography, Palaeoclimatology, Palaeoecology
Volume: 592
ISSN: 0031-0182
DOI: https://doi.org/10.1016/j.palaeo.2022.110903
Publication date: 04-2022
Peer reviewed: Yes
Austrian Fields of Science 2012: 105112 Historical geology, 105123 Stratigraphy, 105101 General geology
Keywords
ASJC Scopus subject areas: Oceanography, Ecology, Evolution, Behavior and Systematics, Earth-Surface Processes, Palaeontology
Sustainable Development Goals: SDG 13 - Climate Action, SDG 14 - Life Below Water
Portal url: https://ucrisportal.univie.ac.at/en/publications/d0af65fb-f225-4f3d-8aae-25852af64723

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