Landslides & Debris Flows
A Dynamic Landscape
"Wilderness" is a word that conjures ideas of ruggedness and timelessness for many people - but the reality is that the wilderness of the far north is surprisingly fragile. The massive landscape of this park - an area half the size of Switzerland - can witness dramatic alterations, such as landslides.
Pretty Rocks Landslide
Section last updated: April 16, 2018
(contingent on funding)
Igloo Debris Slide (2013)
In late October, road maintenance staff discovered that a 600’-long, 110’-wide debris slide had blocked the park road near Mile 38.
The trigger for the slide remains unknown. Ground, aerial, and satellite imagery of the site in the years and months before to the event indicate that a small slide had previously occurred here, groundwater seeped from the area, and the ground was beginning to move slightly (see imagery). In the days preceding discovery of the slide, the area was experiencing temperatures that fluctuated near the freezing point. Therefore, the forces associated with the expansion of ice during the repeated freezing and thawing of water near the surface may have triggered the slide. Alternatively, we also know that a thick layer of permafrost slid on an unfrozen layer of clay.
Last updated: June 25, 2018