G02_P07

The chronology of the sedimentation in the Danube abyssal fan records the major episodes of the late-Holocene Black Sea evolution

Ilie M^1,2,  Sava T¹, Vespremeanu-Stroe A³, Duliu O², Cristea G⁴, Ion G⁵, Olteanu D^1,3, Haliuc A⁶, Manailescu C¹, Sava G¹

¹RoAMS Laboratory, Horia Hulubei National Institute For R&D In Physics And Nuclear Engineering (IFIN-HH), Magurele, Ilfov, Romania, ²University of Bucharest, Faculty of Physics, Magurele, Romania, ³GEODAR Research Center for Geomorphology, Geoarchaeology and Paleo-environments, Faculty of Geography, University of Bucharest, Bucharest, Romania, ⁴Department of Mass Spectrometry, Chromatography and Applied Physics, National Institute for Research and Development of Isotopic and Molecular Technologies, Cluj-Napoca, Romania, ⁵National Institute of Marine Geology and Geo-Ecology (GeoEcoMar), Bucharest, Romania, ⁶Romanian Academy, Institute of Speleology, Cluj-Napoca, Romania

The construction for the high-resolution Bayesian sedimentation model spanning the last 5500 years based on 25 AMS radiocarbon dated sediments of bulk organic matter (OM) sampled from the NW Black Sea anoxic waters of the continental slope is presented in this paperwork. The corrections for the ¹⁴C ages due to marine reservoir effect (MRE) and detritus organic carbon are correlated with exogenous information such as 210Pb dating, metallurgy pollution and human-induced soil erosion, highlighting the Danube influence on the geochemistry and chronology of the NW Black Sea sediments through the input of terrigenous organic matter.

The results show excellent agreement with some of the previous studies, supporting a total age offset for the bulk OM of 60 years as MRE and 580 years as detritus organic carbon influence. The revisited chronology pinpoints the first and second invasion of the coccolitho-phores Emiliania huxleyi at 2524 ± 87 and 625 ± 65 years cal. BP. The sedimentation rate shows an increase of about three times with the starting of the late Medieval, which corresponds to the highest observed sediment discharge of the Danube as are considered the last 500-300 years.

This type of high-resolution sedimentation model is an important step for constructing the carbon budget in bottom waters of variable oxygen concentration.