Migration of Insoluble and Soluble Impurities in Temperate Ice: Study of a Vertical Ice Profile Through the Glacier Du Mont De Lans (French Alps)

• Published in: Journal of Glaciology
• Main Author: Ricq-de Bouard, M.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1977
• Subjects: Earth-Surface Processes; Mont de Lans; Journal of Glaciology
• Online Access: http://dx.doi.org/10.1017/s0022143000021328; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000021328

Abstract Ice samples representing at least some twenty years' accumulation, have been collected from a crevasse wall at 3 200 m (Glacier du Mont de Lans, Massif de l'Oisans), with a view to studying the behaviour of soluble and insoluble impurities in temperate ice. The stratification of the ice from the surface to 2 m and the disappearance of this stratification below 2 m are attributed to a variation in the glacier regime on both sides of the equilibrium line, rather than to a variation in the conditions of deposit of solid debris on the glacier surface, the strata do not necessarily correspond to an annual accumulation. Mineralogical analysis of the solid particles has allowed us to demonstrate two kinds of deposit: that consisting of the local Alpine material (hornblende) and that consisting of a mixture of local material and red sand of Saharan origin (anatase). A study of the distribution of major cations (Na, K, Mg, Ca) along a profile has revealed the existence of a process of leaching which follows an exponential law to a first approximation. The leaching produces a rapid evolution in the chemical properties of the ice compared with those of the original precipitation.