Résumé
West- and Central European Weichselian Upper Pleniglacial loessic deposits (35-17 ka BP) include alternations of loess layers and tundra gleys. Their continental extension implies a formation linked to millennial-timescale global climatic changes, i.e. Dansgaard-Oeschger cycles. The high resolution analysis of the composition of terrestrial malacofaunas from Nussloch allowed the palaeoenvironmental characterization of these sedimentary alternations in the Middle Rhine Valley in Germany. In the present work, two high resolution molluscan records have been performed in northern France, which belongs to a less diversified malaco-biogeographical domain than the Rhine Valley. Results show several environmental phases associated with loess-gley alternations and specific environmental dynamics during the formation of each tundra gley. Correlations are proposed with stadial and interstadial phases of Dansgaard-Oeschger cycles, with the synthetic stratigraphy of northern France loess and with Nussloch tundra gleys. The lack of radiometric ages accompanying these molluscan data is still the main limitation to proposing a detailed chrono-environmental frame for these records in northern France.