L'âge de la capture : corrélation entre les formations fluviales saaliennes de la Haute Moselle et de la Meuse

Résumé En Fr

Age of the capture : corrélations between the Saalian flnviatile formations of the Upper Moselle and the Meuse. — Two middle terraces and two lower terraces are présent in the area of the Moselle Valley, near Toul, where the river was captured. The middle terraces (T 1.1 and T 1.2) border a palaeo-drainage route of the Upper Moselle towards the Meuse. The lower terraces (T 0.1 and T 0.2) are well represented between Toul and Pompey, and belong to the part of the Moselle valley that post-dates the capture. Gravel samples of the four terraces show progressive changes from the highest to the lowest terraces : an increase in basement rocks issued from the Vosges and non-weathered clasts, and a decrease in the percentage of « granité fondamental ». These characteristics indicate that the four terraces correspond with four alluvial formations that can be found upstream in the valley of the Upper Moselle. Formations Fxl. Fx2 and Fx3, are of Saalian âge (Taous, 1994). whereas the last (Fy1.) dates from the Weichselian. The Upper Moselle was captured after the déposition of formation Fx2 which constitutes the lower middle terrace T 1.2 of the Moselle in the area of Toul and corresponds also to siliceous alluvium found at the bottom of the valley fill of the Meuse.

Age of the capture : corrélations between the Saalian flnviatile formations of the Upper Moselle and the Meuse. — Two middle terraces and two lower terraces are présent in the area of the Moselle Valley, near Toul, where the river was captured. The middle terraces (T 1.1 and T 1.2) border a palaeo-drainage route of the Upper Moselle towards the Meuse. The lower terraces (T 0.1 and T 0.2) are well represented between Toul and Pompey, and belong to the part of the Moselle valley that post-dates the capture. Gravel samples of the four terraces show progressive changes from the highest to the lowest terraces : an increase in basement rocks issued from the Vosges and non-weathered clasts, and a decrease in the percentage of « granité fondamental ». These characteristics indicate that the four terraces correspond with four alluvial formations that can be found upstream in the valley of the Upper Moselle. Formations Fxl. Fx2 and Fx3, are of Saalian âge (Taous, 1994). whereas the last (Fy1.) dates from the Weichselian. The Upper Moselle was captured after the déposition of formation Fx2 which constitutes the lower middle terrace T 1.2 of the Moselle in the area of Toul and corresponds also to siliceous alluvium found at the bottom of the valley fill of the Meuse.