Particularités rencontrées dans la région de Montréal résultant de l'arrachement d'écailles de roc par la glaciation

Abstract

Several cases of abrupt changes in the bedrock topography were encountered during the excavation of the Metro extension; they are described briefly and their importance on design from preliminary surveys is discussed. The authors comment on their origin which is related to the low dip of the bedding, the presence of a weak layer at depth, and to the horizontal force exerted by glaciers.