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As one of the major players of the Atlantic meridional overturning circulation, the deep southern component water (SCW), comprising Lower Circumpolar Deep Water (LCDW) and Antarctic Bottom Water (AABW), ventilates the deep waters and influences global climate. However, detailed information about deep SCW strength are lacking, due to its corrosivity resulting in a lack of appropriate paleoceanographic archives. In order to improve the accuracy of ocean circulation variability, detailed deep SCW reconstructions require additional efforts from many branches of climate research. In the frame of this thesis, seven radiocarbon-dated Sediment cores from the Argentine continental margin (i.e. from contourite deposits, the Mar del Plata Canyon and the deep slope) were investigated. The core sites provide the opportunity to investigate the intermediate and deep water mass circulation, e.g. deep SCW flow strength variations, of the deep Southwest Atlantic during the last 20 ka. Furthermore, part of these sediment cores were used to analyze the influence of intermediate and deep ocean currents on sedimentary processes within a blind canyon system.

This thesis focused on sediment dynamics on the East African continental margin and their response to paleoclimatic and sea-level changes on a millennial time scale during the last deglaciation and Holocene. High-resolution Holocene sedimentary records (core GeoB12605-3) from the continental shelf off Tanzania indicate that that there has been a shift in the sedimentation regime during the past 10 ka. During the early Holocene, when climate was humid, sediments were dominated by the allochthonous, fine-grained clay minerals transported by river mouth bypassing. In contrast, during the arid, late Holocene, sediments were dominated by the autochthonous, reworked, coarse-grained quartz and feldspars resulting from shoreface bypassing. For the slope environment, the Rufiji turbidite deposits (core GeoB12624-1) are mainly composed of quartz sand. The turbidity currents were most active during the last sea-level transgression and highstand, when a more humid climate prevailed. Thus, it is the climate conditions of the hinterland that form the primary controlling factor in this environment.