Monday January 22, 2024, 5 pm, CET, GMT +1
Leroy, Suzanne1,2,3 and Marret, Fabienne3
Dinocyst assemblages in MIS 6 and MIS5 of the Sea of Marmara (Turkey) and similarities with the Caspian Sea
1. Aix Marseille Univ, CNRS, IRD, INRAE, Coll France, CEREGE, Aix-en-Provence, France, suzleroy@hotmail.com
2. Aix Marseille Univ, CNRS, Minist. Culture & Com., LAMPEA, 13094 Aix-en-Provence, France
3. School of Environmental Sciences, University of Liverpool, L69 7ZT Liverpool, UK
The Sea of Marmara (SoM) is the connection between the vast Black Sea-Caspian Sea basin (Pontocaspian) and the Global Ocean via the Mediterranean Sea. Its water levels and water conditions have widely varied over times. Combining two cores in the SoM and using organic-walled dinoflagellate cyst assemblages as the main proxy (combined with alkenones and benthic foraminifera), allow qualitatively reconstructing water conditions during Marine Isotopic Stage (MIS) 6 and 5, such as salinity and oxygen level. A clear main marine phase is illustrated in MIS 5e. A minor marine incursion occurred during MIS 5c, mostly supported by alkenone data. The rest of the record indicates brackish Pontocaspian conditions, with more Spiniferites inaequalis in MIS 6 and more S. cruciformis in the non-marine parts of MIS 5.
At the MIS 6/MIS 5 transition, an earlier initial marine flooding in the SoM (dinocyst assemblages) in comparison to the Black Sea was highlighted. The marine reconnection occurred at different moments as seen in the terrestrial vegetation reconstructed from pollen analysis linking the two seas.
Many dinocyst taxa newly identified in the Caspian Sea, such as Caspidinium rugosum and Impagidinium caspienense, were also found in the brackish phases of the SoM.