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Observer Name: 
Greg Gagne
Observation Date: 
Sunday, November 19, 2017
Occurrence Date: 
Saturday, November 18, 2017
Region: 
Catherine's Pass
Location Name or Route: 
Catherine's Pass Area
Elevation: 
10100
Aspect: 
North
Slope Angle: 
38
Trigger: 
Unknown
Avalanche Type: 
Soft Slab
Avalanche Problem: 
Persistent Slab
Weak Layer: 
Facets
Depth: 
2'
Width: 
70
Vertical: 
80
Comments: 

Noticed this slide in Catherine's Pass area on Sunday - second slide I found in this area this weekend. I did not notice it on Saturday (may have missed it) and there was no storm snow on top. No tracks above or adjacent to the slide, however I did see a single ski track below the slope, and am guessing it may have been remotely triggered.

This slide failed on a layer of facets sitting just above a thermal crust from September.

Comments: 

Photo of slide with an arrow pointing to the dirty graupel layer from the onset of Friday's storm.

Comments: 

This photo at the crown showing how stress cracks propagated widely, but did not avalanche as the angle of the slope lessened.

Comments: 

In a Sherlock Holmes moment, am guessing this was remotely triggered as if it was a natural during the storm, there would have been some storm snow on top of the bed surface and the debris from the tail end of the storm.

This also fits the characteristics of a persistent slab weakness: (1) remote triggering from the flats that (2) propagates widely.

Coordinates: 
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