Valenti Chloé, Rinterknecht V., Koehler H., Griselin S., Audouard L., Gehres B., Couette P. O., Aster E. (2024). Déglaciation des Vosges gréseuses et reconstructions paléoclimatiques à partir de datations par le béryllium-10 produit in situ. Quaternaire, 35 (1), 3-16. ISSN 1142-2904.
Titre du document
Déglaciation des Vosges gréseuses et reconstructions paléoclimatiques à partir de datations par le béryllium-10 produit in situ
Valenti Chloé, Rinterknecht V., Koehler H., Griselin S., Audouard L., Gehres B., Couette P. O., Aster E.
Source
Quaternaire, 2024,
35 (1), 3-16 ISSN 1142-2904
In the context of global ice retreat, studying glaciers and glacier responses to present and past climatic variations provies information to understand their long-term evolution. Alpine and Pyrenean glaciers have been the subject of paleoclimate studies but it is not the case of the Vosges Gréseuses (VG), a low to medium elevation mountain range in northeastern France. This project focuses on the analysis of the palaeoglaciers of this area, where many landforms suggest the presence of ice during colder periods. We determined the locations of the paleoglaciers and mapped them by using the software ArcGIS and the tool "GlaRe" (Glacier Reconstruction). We show that glaciers in the VG were not extensive and did not exceed 45 m thick. We also dated moraines closest to the cirques using the cosmogenic 10 Be and confirmed that glaciers were indeed present in this area between 19.5 and 13.0 ka. Climatic reconstructions, obtained from Equilibrium Line Altitude (ELA), show that mean summer temperatures were between 1.8 and 2.4 degrees C, when considering precipitations equivalent to the current level. Glaciers retreated before the Younger Dryas (YD) due to their small size, which differentiates them from the Vosges Cristallines, where deglaciation occurred later. Finally, initial dating of the Rocher de Mutzig, one the highest point of the VG, shows that an ice cap probably covered the massif until 38.000 years ago. In a context of cold climatic episodes, it is interesting to link the glacial evolution and prehistoric population dynamics, that must have adapted to paleoclimatic conditions, closing of strategic paths and decreasing availability of ressources.
Plan de classement
Sciences du milieu [021]
;
Hydrologie [062]
;
Géologie et formations superficielles [064]
