| Summary: | The Sr-Nd-Pb isotope composition of siliciclastic sediments from the marine sediment core PS72/287-3 from Barrow Strait was analyzed to identify changing sediment provenances during the last deglaciation and the Holocene. Barrow Strait was blocked by the confluent Laurentide and Innuitian ice sheets during the last glacial period and is hence very interesting to study deglaciation processes in the Canadian Arctic. Varying Sr and Nd isotope ratios during the deglacial period suggest changing sediment sources probably related to ice sheet dynamics and sediment transport processes. After the deglacial period, radiogenic isotope ratios evolved less variable, indicating just slight changes in sediment provenance related to more stable environmental conditions during the Holocene. Sample preparation and radiogenic isotope analysis were conducted in the laboratories of the Isotope Geochemistry Group at MARUM – Center for Marine Environmental Sciences, University of Bremen, Germany. Sediment samples were leached using a NaOH-buffered solution of hydroxylamine hydrochloride and 15% acetic acid in order to separate the siliciclastic sediment fraction (adapted from Gutjahr et al. 2007, https://doi.org/10.1016/j.chemgeo.2007.03.021). Using a Thermo-Fisher Scientific TRITON Plus thermal ionization mass spectrometer (TIMS), the isotope ratios were determined after the elements had been separated by column chemistry.
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