Landslide Hazards along River Corridors - Alpine fans less likely subject to debris flows

Depositional fans are formed when sediment moving down a steep channel is deposited where the channel gradient abruptly decreases, for example where a steep valley-wall tributary reaches the valley floor. Sediment can be carried down such a steep channel in flow-type landslides (debris flows, debris floods) or as sediment can be carried by streamflow. Fans are subject to a range of hazards depending which of the preceding processes are active. Debris flows are a style of landslide movement that entail landslide debris moving in a fluid state down a channel, often travelling a long distance from the point of origin. This layer represents fans that are located in alpine areas and are less likely subject to debris flows.