Tracing past and present Arctic geochemical cycling and its link to climate change using neodymium isotopes ...

• Main Author: Larkin, Christina
• Format: Thesis
• Language: English
• Published: Apollo - University of Cambridge Repository 2020
• Subjects: Arctic; Paleoceanography; Geochemistry; FOS Earth and related environmental sciences; Weathering; Climate change; Nordic Seas
• Online Access: https://dx.doi.org/10.17863/cam.68663; https://www.repository.cam.ac.uk/handle/1810/321544

The Arctic is one of the most important locations for past and present global environmental change, containing arguably the largest concentration of critical components in the Earth’s climate system. In the past, the Arctic region experienced abrupt changes in both climate and ocean circulation. Neodymium isotope ratios (εNd) have been used extensively as a tracer of continental crustal evolution and in sediment and seawater provenance studies. In this thesis εNd is measured on a suite of marine and terrestrial sediment and waters, broadly focused on the circum-Arctic region, providing insights into both past and current water and sediment sources. A large compilation of εNd in authigenic phases of deep-sea sediments is used to investigate past changes in deep water sourcing and formation in the Nordic Seas from the last glacial to modern. During the Last Glacial Maximum, εNd in the Nordic Seas is found to have a similar homogeneity to the late Holocene and modern, suggesting similar advective circulation ...