Grain size distributions within the proglacial area of the Bossons glacier (France)


This dataset presents grain size distributions within the Bossons glacier proglacial area. Bossons glacier is rapidly retreating and its proglacial area is deglaciated for ~30 years. It is an intriguing location to study periglacial and proglacial erosion processes which requires to characterize proglacial sediments. Such characterization have been previously carried out by Maizels (1976). Grain Size Distribution (GSD) of 13 proglacial sediment samples have been determined by in situ sieving and laser micro-granulometry in laboratory. Samples are located on a longitudinal profile of Bossons stream alluvial plain. In upstream part of the alluvial plain, volume occupied by the largest clast gives the sample volume needed for a reliable GSD analysis. Every GSD was performed on an active gravel bar except for Av3 which was carried out in a perenial and vegetalized one. GSD on the whole area is coarse and mainly constituted by small and large pebbles (~40% of each sample). Silts are almost inexistent (2%). Gravels are generally less present than sands, respectively 8% and 12%. This lack of gravel is commonly observed and is explained by fracturation processes : particles coarser than 5 mm are mainly rock fragments disaggregating into monomineral grains which are inferior to 2 mm (Maizels, 1976). Straightforward GSD analysis shows a grain size reduction toward the outlet of the alluvial plain. From upstream to downstream, each granulometric class seems to follow the same general variations : sand particles increase from 6% upstream to 20% downstream whereas coarse pebbles decrease from 57% to 20%.

Related Identifier
Related Identifier
Metadata Access
Creator Godon, Cécile; Guillon, Hervé ORCID logo; Buoncristiani, Jean-François; Mugnier, Jean-Louis
Publisher PANGAEA
Publication Year 2013
Rights Creative Commons Attribution 3.0 Unported;
OpenAccess true
Resource Type Dataset
Format text/tab-separated-values
Size 221 data points
Discipline Earth System Research
Spatial Coverage (6.849W, 45.897S, 6.852E, 45.899N); Bossons Glacier, Massif du Mont-Blanc, Haute-Savoie, France