Quaternary landscape evolution of the river Seine (France): Synthesis and new results from ESR dating and magnetostratigraphy of fluvial and cave deposits
Résumé
In this paper we present a detailed Quaternary evolution model of the Seine valley (France). The lower Seine valley contains very specific preserved morphological features (semi-entrenched meander cut-offs) and develops in a karstified chalky plateau (Normandy Chalk). Regional geomorphological features make it possible to combine geomorphological observations, petrological investigations as well as cross-dating analysis of fluvial sediments and karstic archives. We have reviewed former chronological data through a combination of different dating methods including ESR, U-series as well as palaeomagnetism. We also present here new dating results from both cave deposits and fluvial terrace sediments through the combined use of quartz ESR dating method and palaeomagnetism. The obtained results show river evolution extending over the entire Quaternary period. The gentle incision rate and its variations highlight the influence of climate and eustatic processes, hence a partially climate-induced uplift. Results also provide new chronological markers on the fluvial deposits for future archaeological research.