Sr, Nd, and Pb isotope provenance of surface sediments on the East Siberian Arctic Shelf and implications for transport pathways

• Published in: Chemical geology Vol. 618; p. 121277
• Main Authors: Li, Qiuling, Qiao, Shuqing, Shi, Xuefa, Chen, Yufei, Astakhov, Anatolii, Zhang, Hui, Hu, Limin, Yang, Gang, Bosin, Alexander, Vasilenko, Yuri, Dong, Linsen
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 20.02.2023
• Subjects: Arctic sea ice; Chukchi Sea; East Siberia Sea; Laptev Sea; Sediment provenance; Sr-Nd-Pb isotopes; Arctic sea ice; Sr-Nd-Pb isotopes; Laptev Sea; East Siberia Sea; Chukchi Sea; Sediment provenance
• ISSN: 0009-2541; 1872-6836
• DOI: 10.1016/j.chemgeo.2022.121277

The East Siberian Arctic Shelf (ESAS) is a crucial area for sea ice formation and exportation in the Arctic Ocean. Precise sedimentary identification in the ESAS is vital to trace sea ice transport. However, tracking sea ice transport is challenging due to the complexity of the sediment sources and transport processes in the ESAS. In this study, we investigated Sr, Nd, and Pb isotopes in residual fractions of recent surface sediments in the ESAS to explore the distribution, sources, and transport pathways of terrigenous materials and track regional sea ice transport. Our results show that approximately 20–30% of the Western Laptev Sea (WLS) sediments were derived from Siberian flood basalt, characterized by a high εNd (ca. -9.0) and a high 87Sr/86Sr ratio (ca. 0.715). Furthermore, most sediments of the Eastern Laptev Sea–Western East Siberian Sea (ELS–WESS) were derived from ancient clastic and metamorphic rocks, with the lowest εNd values (ca. -12.3), highest 87Sr/86Sr ratios (ca. 0.717), and highest 207Pb/206Pb ratios (ca. 0.836). Additionally, sediments in the Eastern East Siberian Sea–Western Chukchi Sea (EESS–WCS) had the highest εNd values (ca. -7.6), lowest 87Sr/86Sr ratios (ca. 0.712), and relatively high 207Pb/206Pb ratios (ca. 0.830) due to the influence of Okhotsk–Chukotka volcanic belt (OCVB) weathering products, which contributed approximately 10–20% of the local sediments. Eastern Chukchi Sea (ECS) sediments showed relatively low εNd values (ca. -9.2), low 87Sr/86Sr ratios (ca. 0.712), and the lowest 207Pb/206Pb ratios (ca. 0.810), which probably influenced by coast erosion inputs from Alaska and Yukon River material transported via Pacific Sea Water. Based on the sediment provenance with Nd isotope, sea ice formed in the WLS and ELS–WESS is predominantly transported by the Trans-Polar Drift (TPD) to the Eurasian Basin and Fram Strait. This study provides insights for further understanding and tracking sea ice transport processes from the ESAS to the Arctic Ocean. •Western Laptev Sea sediments are derived from Siberian flood basalt and old crust.•Eastern East Siberian Sea sediments are influenced by Okhotsk–Chukotka volcanic belt.•Eastern Laptev Sea and Western East Siberian Sea are the primary sources of sea ice sediment in the Eurasian Basin.•The combination of SrNd isotopes and smectite can improve the sediment source identification in the Arctic.