Long-term evolution of late Pliocene to mid-Pleistocene bottom current regime in response to intermediate water circulation in the NE-Atlantic

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The proposed project will elaborate a long-term history of Pliocene-Pleistocene palaeocurrent strength in response to deep and intermediate water formation close to one of the main locations of NADW production from drift sediments in the North Atlantic. Recent progress in unravelling ice-rafted debris of silt size from bottom current transported fine sediments will be used to establish a reliable palaeocurrent record, and thus the variability and evolution in current strength during times of significant environmental changes. Detailed grain-size analysis of the fine sand and silt fraction will provide the base for the end-member modelling, a mathematical-statistical approach to unmix sediments of distinct size fractions but different in their origin. By the differentiation of silt-sized ice-rafted bias from bottom current sediment transport, we will be able to integrate the results from the high-latitude oceans in Pliocene/Pleistocene deep-water formation and palaeocurrent strength reconstructions regions further downstream in the thermohaline circulation loop for a better insight into the physical flow regime of this global system.