Response of the Rhine-Meuse fluvial system to Saalian ice-sheet dynamics

• Published in: Boreas
• Main Authors: Busschers, Freek S., Van Balen, Ronald T., Cohen, Kim M., Kasse, Cees, Weerts, Henk J.T., Wallinga, Jakob, Bunnik, Frans P.M.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2008
• Subjects: Life Science; Dover; Ice Sheet
• Online Access: https://research.wur.nl/en/publications/response-of-the-rhine-meuse-fluvial-system-to-saalian-ice-sheet-d; https://doi.org/10.1111/j.1502-3885.2008.00025.x

A new reconstruction of the interaction between the Saalian Drente glaciation ice margin and the Rhine-Meuse fluvial system is presented based on a sedimentary analysis of continuous core material, archived data and a section in an ice-pushed ridge. Optically Stimulated Luminescence (OSL) was applied to obtain independent age control on these sediments and to establish a first absolute chronology for palaeogeographical events prior to and during the glaciation. We identified several Rhine and Meuse river courses that were active before the Drente glaciation (MIS 11-7). The Drente glaciation ice advance into The Netherlands (OSL-dated to fall within MIS 6) led to major re-arrangement of this drainage network. The invading ice sheet overrode existing fluvial morphology and forced the Rhine-Meuse system into a proglacial position. During deglaciation, the Rhine shifted into a basin in the formerly glaciated area, while the Meuse remained south of the former ice limit, a configuration that persisted throughout most of the Eemian and Weichselian periods. An enigmatic high position of proglacial fluvial units and their subsequent dissection during deglaciation by the Meuse may partially be explained by glacio-isostatic rebound of the area, but primarily reflects a phase of high base level related to a temporary proglacial lake in the southern North Sea area, with lake levels approximating modern sea levels. Our reconstruction indicates that full 'opening' of the Dover Strait and lowering of the Southern Bight, enabling interglacial marine exchange between the English Channel and the North Sea, is to be attributed to events during the end of MIS 6.