Composite flowslide-spread landslides in Eastern Canada

The most common highly retrogressive landslides in Eastern Canada sensitive clays are flowslides and lateral spreads. Quebec’s post-glacial sensitive clay deposits are typically exposed to these two phenomena, which generally occur independently, but the well-documented 2016 landslide at St-Luc-de-Vincennes has shown that both processes causing these hazards can occur in the same event. The aim of this article is to draw up an inventory of historical composite flowslide-spread landslides. The exercise enables us to list all the characteristics that are present at these sites when the two phenomena are combined.