Newly acquired high-resolution multibeam bathymetry, seismic reflection and sedimentological data allowed to investigate the architecture evolution and depositional patterns since the Oligocene in order to understand the main forcing factors that control the deep sea sedimentation in the Mozambique Channel. The Zambezi turbidite system (Mozambique Channel, Western Indian Ocean) is one of the largest turbidite systems in the world and yet still remains poorly understood. Finally, foraminifera depict the mid‐HS2 reventilation event due to regional glacier instabilities. This is consistent with the fact that HS1 was by far the most important period of ice‐sheet retreat and meltwater release into the ocean over the studied time interval. HS1 is distinctive for its abundance of high‐organic flux indicator species during its early phase. This confirms an overall sluggish intermediate circulation during the three HSs in the northeast Atlantic. In general, HSs were characterised by the concomitant presence of meso‐oligotrophic and anoxia indicator species and the low abundance of high‐energy indicator species.
Our results highlight the high sensitivity of foraminifera, with species‐specific responses, to continental (European Ice Sheet dynamics) and marine (AMOC) forcing factors during the last three HSs. Here we use benthic foraminiferal assemblage data to trace palaeoenvironmental changes from ~32 to 14 ka cal bp at ~1000 m depth in the Bay of Biscay. Compared with the surface and deep regions of the Atlantic Meridional Overturning Circulation (AMOC), the study of intermediate depths during key time periods, such as Heinrich Stadials (HSs), remains poorly documented, especially for the northeast Atlantic. The interaction between ocean circulation and ice‐sheet dynamics plays a key role in the Quaternary climate.
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