Lead


Lay summary
Because of its geographical location and setting, the Mediterranean Sea, acts as a paleo-environmental amplifier and as a sensitive recorder for environmental changes. The basin is connected at East with enclosed sub-basins with complex histories and characterized by peculiar environmental settings: the Tethyan relict basins (Marmara and Black Seas). To the West the Mediterranean Sea connects to an open ocean: the Atlantic.This project aims to investigate the Mediterranean connections in the last 150.000 years. It is focused to complete with the additional fourth year an on-going thesis on the Eastern Mediterranean -Black Sea connections (thesis of G. Gennari).Despite the extraordinary number of researches that deal with the late Pleistocene-Holocene paleoceanography history of this region, there are still several hotly debated topics without a clear documentation and explanation. With this project we aim to investigate the nature and mechanisms that controlled the Mediterranean - Black Sea connections during the last 30.000 years, that is from the dawn of human civilization to the present days focusing on the region around the Bosphorus Strait, the Sea of MArmara and the Eastern Mediterranean. This multidisciplinary study include: (1) paleontological studies of benthic and planktonic foraminiferal assemblages from cores in the Estern Mediterranean, Marmara and Black Sea. (2) Geochemical studies of oxygen and carbon isotopes of foraminiferal shells, phosphorus and organic matter in sediments as well as XRF, of cores and (3) AMS14C dating.Easter Mediterranean: The results of the previous project include the identification of high-frequency millennial to decennial-scale solar cycles centered at 1700, 550, 210, 85-70, 60 and 50 years, suggesting that also during sapropel S1 deposition, climate in the Mediterranean region was paced by solar variability even at short periodicities confirming the strong sensitivity of Mediterranean climate even at a decennial scale.Black Sea: Three lithological units have been identified in sediments in front of the Bosphorus Strait. From bottom to top theyare: 1) an alternation of light and dark lutite (lacustrine deposits); 2) an organic-rich sapropel layer; 3) an alternation of light and dark microlaminae (coccolith ooze). Although these lithological units are usually not recognizable in shelf sediments due to their high sedimentological variability, calcareous nannoplankton ecozones have recently been used for wide shelf-basin correlations, tracking the shift from fresh/brackish to low-salinity marine conditions.