Les risques naturels d'origine glaciaire: inventaire dans les Alpes françaises et typologie

Natural risks of glacial origin : an inventory in the french Alps and typology

Cemagref, Etna et L.G.G.E., C.N.R.S., Grenoble

Abstract

Several terrain investigations, with specialized organizations such as services R.T.M., the P.G.H.M., allow us to count nearly 100 events which have occurred in the French Alps during 200 last years. The whole of this inventory has been centralized and synthesized in the form of data sheets; each glacier having presented at least one event has a data sheet, containing a description of the glacier (localization and a photograph), and the description of the various listed events. The data sheets were gathered by massif (Mont Blanc, Vanoise, Ecrins and the South Alps massif). After having indexed the events of glacial origin, it appeared necessary to classify them; 3 principal categories thus are distinguished:

- drainings of glacial lakes,

- falls of ice (distinguishing the falls from seracs, repetitive, from the glacial tongues ruptures or the falls of suspended glaciers, much rarer),

- ruptures of water pockets.