Regarding the previous posts of large avalanches observed in the Asulkan Valley. Yesterday, the Parks Canada avalanche control team at Rogers Pass went to investigate the Dome Glacier avalanche that occurred on Nov 20th. It was classified as a size 3.5 that ran 700m right down to tree line. It was 200m wide, with a maximum depth of 2m and an average depth of 1.1m.
Most importantly is that it failed on the November 12 surface hoar layer size 4-8mm. It is a 1 cm thick layer in that location and can be seen in the attached photo. It's sitting on a 12cm facet layer, the top of which was the bed surface for this avalanche.
The surface hoar layer was 100cm where we dug and is 70cm above the glacial ice. This confirms that there is a persistent weak layer in the alpine in this region.
Also interesting was the presence of a 3cm hard crust below the facets.
The height of the snowpack on and around the glacier was variable between 1.5m to 2.8m with many crevasses still visible.
There is new surface hoar growing at this time into the alpine waiting to be buried.
Avalanche Control and Visitor Safety Team
Mt. Revelstoke and Glacier National Parks
Parks Canada
via
Peter Tucker
Executive Director
B: +1.403.949.3587
M: +1.403.689.4324
ed@xxxxxxx | www.acmg.ca
