High resolution molluscan records in Upper Weichselian loess and tundra gleys: first examples from northern France
International audience 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...
Published in: | Quaternaire |
---|---|
Main Authors: | , , , |
Other Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | French |
Published: |
HAL CCSD
2011
|
Subjects: | |
Online Access: | https://inrap.hal.science/hal-02055105 https://inrap.hal.science/hal-02055105/document https://inrap.hal.science/hal-02055105/file/Moine%20et%20al.%202011.pdf https://doi.org/10.4000/quaternaire.6042 |
Summary: | International audience 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-biogeo-graphical 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. Les dépôts loessiques du Pléniglaciaire supérieur weichselien (~35-17 ka BP) d'Europe de l'ouest et centrale sont constitués par des dépôts de loess calcaires entrecoupés par plusieurs niveaux de gleys de toundra. Leur extension continentale implique une formation liée à des variations millénaires du climat global, i.e. cycles de Dansgaard-Oeschger. L'analyse à haute résolution de la composition des malacofaunes terrestres de Nussloch a permis la caractérisation paléoenvironnementale de ces alternances sédimentaires en Allemagne dans la moyenne vallée du Rhin. Dans le présent travail, deux enregistrements malacologiques à haute résolution ont été réalisés dans le nord de la France qui appartient à un domaine malaco-biogéographique moins diversifié que celui de la vallée du Rhin. Les analyses ont permis la ... |
---|