Dating fluvial erosion: fluvial response to climate change in the Moselle catchment ( F rance, G ermany) since the L ate S aalian

This paper focuses upon the youngest terraces of the M oselle and its tributary the M eurthe ( NE F rance and SW G ermany). It includes research on several sections, in particular the key sections of G olbey‐ P ré D roué and T hörnich‐ H ochrech (located in the vicinity of the V osges M assif and in the R henish M assif, respectively), and the use of the O ptically S timulated L uminescence ( OSL ) dating method. Our investigations made it possible to obtain a more robust chronostratigraphical framework and to update the previous model of fluvial response to climate change. The results demonstrate that the M oselle terrace M 3 (first terrace formed after the capture of the U pper M oselle by the P alaeo‐ M eurthe) has the same age from the V osges to the R henish M assif. The formation of this terrace included two main periods of sedimentation attributed to the L ate S aalian ( MIS 6) and the E arly W eichselian ( MIS 5), respectively. They were separated by a major episode of fluvial erosion that may be allocated to the MIS 6–5 transition on the basis of chronological and sedimentological evidence. This erosion led to the removal of most of the MIS 6 deposits, whereas the MIS 5 deposits have been widely preserved following the subsequent ( MIS 5–4) terrace incision. This evolution somewhat contrasts with that observed in the S arre valley, the main tributary of the M oselle, and with many fluvial systems in western Europe, which show better preservation of deposits from cold periods. This atypical behaviour is explained by the relationship between the fluvial evolution and the glaciers covering the upper M oselle catchment ( V osges M assif) during the P leistocene cold periods.