The Sea of Marmara during Marine Isotope Stages 5 and 6

• Published in: Quaternary Science Reviews
• Main Authors: Çağatay, M. Namık, Eriş, K. Kadir, Makaroğlu, Özlem, Yakupoğlu, Nurettin, Henry, Pierre, Leroy, Suzanne A.G., Uçarkuş, Gülsen, Sakınç, Mehmet, Yalamaz, Burak, Bozyiğit, Cerennaz, Kende, Julia
• Other Authors: Istanbul Technical University (ITÜ), Istanbul University, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Avrasya Yerbilimleri Enstitüsü
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2019
• Subjects: Sea of Marmara; Late Quaternary; Marine Isotope stages 5-6; Eastern Europe; Paleoceanography; Sedimentology-marine cores; Geochemical proxies; Sapropels; [SDU.STU]Sciences of the Universe [physics]/Earth Sciences; [SDU.STU.GC]Sciences of the Universe [physics]/Earth Sciences/Geochemistry; [SDU.STU.ST]Sciences of the Universe [physics]/Earth Sciences/Stratigraphy; NGRIP; North Atlantic
• Online Access: https://hal.archives-ouvertes.fr/hal-02415856; https://hal.archives-ouvertes.fr/hal-02415856/document; https://hal.archives-ouvertes.fr/hal-02415856/file/JQSR_2019_423_SL_080719_sans.pdf; https://doi.org/10.1016/j.quascirev.2019.07.031

International audience Multi-proxy analyses and lithology of two cores, MRS-CS18 and MRS-CS27, from the İmralı Basin of the Sea of Marmara (SoM) provide important new information on environmental conditions, relative sea level, and sill depths of the straits of Bosporus and Dardanelles during the marine isotope stages (MIS) 5 and 6. The fossil and multi-proxy geochemical records show that lacustrine conditions prevailed in the SoM during most of MIS-6, from 173 to 134 ka BP, and that the transition to marine conditions during Termination II took place at~134.06±1.10 ka BP. MIS5 interstadials a, c, and e witnessed the formation of three sapropels (MSAP-4, MSAP-3 and MSAP-2) under suboxic to anoxic marine conditions, whereas during stadials MIS5b (~94-86) and MIS5d (~112-105 ka BP), lacustrine and marine conditions with deposition of sediments having relatively low TOC contents (<2 %) prevailed, respectively. Consideration of the global sea level, together with the timing of the marine reconnection of the SoM during Termination II and persistence of the marine conditions during MIS5, except for the MIS5b, suggests that the Dardanelles sill depth was at~-75±5 m during the reconnection at Termination II and at-55±5 m during most of MIS5. On similar considerations of the Black Sea marine reconnections and disruptions during the MIS5, a sill depth of-35 to-40 m (similar to the present day depth) is indicated for the Bosporus Strait. The SoM geochemical proxy records correlate well with the regional terrestrial and marine records and the NGRIP oxygen isotope record with its glacial and interglacial (GI) phases, showing the common effect of the North Atlantic climatic events triggered by the perturbations in the Atlantic Meridional Overturning Circulation (AMOC). However, the amplitude of the oscillations recorded in the SoM during MIS6 (Penultimate Glacial Period) is relatively smaller compared to the MIS4 to MIS2 (Last Glacial Period).