Sedimentological analysis of sediments from Amundsen and Bellingshausen Seas, Southern Ocean

Glaciomarine deposits at the Antarctic continental margin represent an important paleoglaciological and paleoceanographical record of environmental changes in both Antarctica and the adjacent Southern Ocean. In order to reconstruct the climatic-controlled sedimentation history in the Amundsen and Bellingshausen Seas during Quaternary glacial cycles, sedimentological, geochemical and clay mineralogical investigations were carried out on 34 surface sediment samples and On 7 sediment cores. The study of the surface sediment samples allows one to decipher the recent sediment supply and transportation processes. The input of glacial debris is highest in the eastern Bellingshausen Sea because of the subpolar climatic conditions prevailing over the adjacent Antarctic Peninsula. Fine sediment pathways of transport in the Amundsen and Bellingshausen Seas were recon- structed by analysing the clay mineralogical composition of the surface sediments and connecting it with specific source rocks in the West Antarctic hinterland. Grain size data show a complex dispersal Pattern of ice-rafted debris (IRD). According to these data, redeposition by currents plays a major role near the shelf break both in marginal seas and on the continental rise in the eastern Bellingshausen Sea.
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