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Titre Débit des eaux de fonte, charges sédimentaires et taux d'érosion dans le massif du Mont-Blanc
Auteur Judith K. Maizels
Mir@bel Revue Revue de Géographie Alpine
Numéro vol. 66, no 1, 1978 Comptes rendus critiques
Page 27 pages
Résumé anglais Abstract. — The timing and duration of the meltseason has been objectively determined for five Mont-Blanc glaciers by defining critical minimum flow values of the glacial meltwaters. The smaller glaciers experienced far longer "meltseasons" than the larger glaciers, as annual melting extended more quickly to the more distant parts of the smaller basins. Significant correlations were found to exist between the surface area of each of the five glaciers and their mean meltwater discharge for each month ; interpolation from these relationships allowed the probable annual regime of meltwaters from the neighbouring, but unmonitored, Bossons Glacier, to be predicted. Measurements of sediment amounts removed by meltwaters from the Bossons Glacier suggest that the granite and schist bedrock is eroded at the rate of 600 to 900 mm per 1000 years. About 60 per cent of this amount appears to have been removed in suspension, compared with about 23 per cent as bedload and 1 per cent in solution, while about 16 per cent of the fluvioglacial debris eroded from the Bossons Glacier basin has been deposited to form a proglacial valley-train. Some problems involved in making estimates of rates of glacio-hydrological erosion are also discussed.
Source : Éditeur (via Persée)
Article en ligne https://www.persee.fr/doc/rga_0035-1121_1978_num_66_1_2113