Le glissement boueux de La Salle-en-Beaumont (8 janvier 1994) (The earth flow at La Salle-en-Beaumont, 8th January 1994)

Résumé En Fr

- During the night from the 7 th to the 8 th of January 1994, a slope movement occured just above the main locality of La Salle-en-Beaumont in Isère (France). Ground and landforms analysis demonstrate that a rapid earthf-low took place in 10 minutes. Its volume is about one million metric cubes. These slopes were known as stable and no ground movement had been registered before. This earth-flow started thanks to the saturation of a small and local substrat of glacial and glacio-lacus- trine deposits covered by recent colluvium. This unexpected flow was made possible by meteorological data : the last months of 1993 have been very rainy (twice the normal) and heavy rains took place again during the last three days : they determinate a catastrophic event where human impact on the natural environnement have no place.

- Dans la nuit du 7 au 8 janvier 1994, au-dessus du centre de La Salle-en-Beaumont, Isère (France), un glissement boueux ou coulée de terre rapide d'un volume voisin du million de mètres cubes, se met en place en une dizaine de minutes. Sous l'effet de la saturation en eau d'une poche d'argiles glaciaires masquées par des colluvions. Les conditions climatiques (trimestre très arrosé et pluies diluviennes les jours précédents) ont joué un rôle déterminant dans cette catastrophe soudaine et imprévue.