Stratigraphic record reveals contrasting roles of overflows and underflows over glacial cycles in a hypersaline lake (Dead Sea)

Lu, Yin; Pope, Ed L.; Moernaut, Jasper; Bookman, Revital; Waldmann, Nicolas; Agnon, Amotz; Marco, Shmuel; Strasser, Michael

Abstract

In lakes and oceans, links between modern sediment density flow processes and deposits preserved in long-term geological records are poorly understood. Consequently, it is unclear whether, and if so how, long-term climate changes affect the magnitude/frequency of sediment density flows. One approach to answering this question is to analyze a comprehensive geological record that comprises deposits that can be reliably linked to modern sediment flow processes. To address this question, we investigated the unique ICDP Core 5017-1 from the Dead Sea (the largest and deepest hypersaline lake on the Earth) depocenter covering MIS 7-1. Based on an understanding of modern sediment density flow processes in the lake, we link homogeneous muds in the core to overflows (surface flood plumes, ρflow<ρwater), and link graded turbidites and debrites to underflows (ρflow>ρwater). Our dataset reveals (1) overflows are more prominent during interglacials, while underflows are more prominent during glacials; (2) orbital-scale climate changes affected the flow magnitude/frequency via changing salinity and density profile of lake brine, lake-level, and source materials.

Citation

Lu, Y., Pope, E. L., Moernaut, J., Bookman, R., Waldmann, N., Agnon, A., Marco, S., & Strasser, M. (2022). Stratigraphic record reveals contrasting roles of overflows and underflows over glacial cycles in a hypersaline lake (Dead Sea). Earth and Planetary Science Letters, 594, Article 117723. https://doi.org/10.1016/j.epsl.2022.117723

• Journal Article Type: Article
• Acceptance Date: Jul 7, 2022
• Online Publication Date: Jul 21, 2022
• Publication Date: Sep 15, 2022
• Deposit Date: Aug 17, 2022
• Publicly Available Date: Aug 17, 2022
• Journal: Earth and Planetary Science Letters
• Print ISSN: 0012-821X
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 594
• Article Number: 117723
• DOI: https://doi.org/10.1016/j.epsl.2022.117723
• Public URL: https://durham-repository.worktribe.com/output/1194315