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Wednesday, November 2, 2011

[MCR] Selkirk Mtns - Rogers Pass - Bruins Pass Nov.2/2011

Greetings early season keeners,

 

I couldn’t afford a helicopter, so went for a tour with fellow guide Anne Keller up Connaught Ck. today, eventually  ending up at Bruins Pass via 8812 bowl.

 

Weather was broken cloud with no snowfall, and I noted moderate wind transport from the west along the higher Alpine ridges (above 2300m.)

 

Quite good early season coverage (emphasis on EARLY), with @60-80cms of snow in the valley bottom and upwards of 120cms once you are above 2000m.

 

The snowpack feels like a typical well settled early season snowpack, with no significant shears observed.

 

There are 2 exceptions to the above statement:

- one is some isolated wind slabs (approx. 10cms thick) that had formed higher up where the wind had some effect, may be more prominent in the higher alpine which I didn’t observe.

 

-  the second, which is more of a concern, is a well developed Surface Hoar layer(those feathery crystals that form on the surface during clear calm weather). This layer formed in October and was probably buried October 20th – we observed this layer in a profile done Oct.27/2011 at 2300m. on McCrae Pk. (@ 30km. south of Revelstoke in the Selkirks)

 

– (I know not everyone is familiar with this all these test – but I include it for those who are)- we found well preserved crystals 10-15mm. in size positioned 45cms from the ground, which produced clean shears(Sudden Planar) in 2 compression test at the high end of the moderate range, we also tried an Extended Column test which did not propagate across the wider column – then we did a Propagation Saw test which failed once we had cut just 25cms into the weak layer and the failure propagated to the end of the column.

 

-          What that means to me is that I would be a bit leery of steeper glaciated features above 2300m. (like Youngs Peak Headwall and Mt. Rogers), until I get a better handle on the distribution and reactivity of this layer.

No significant avalanche activity observed today.

 

Cheers,

Scott Davis

ACMG/IFMGA Mountain Guide

 

 

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