Avalanche: 4th Sister Ridge, low 1/21/2010

Thu, 01/21/2010 - 10:22pm
Submitted by Toby
Observer Name: 
anonymous
Observation Date: 
01/21/2010
Occurrence Date: 
01/21/2010
Occurrence Time: 
11:00am
Region: 
4th Sister Ridge, low
Cottonwood
Logan River
Logan

Location

41° 52' 5.1276" N, 111° 39' 59.238" W
Avalanche Characteristics
Elevation: 
8000'
Aspect: 
North
Slope Angle: 
35
Alpha Angle: 
32
Trigger: 
Snowboarder
Trigger: additional info: 
Unintentionally Triggered
Avalanche Type: 
Hard Slab
Weak Layer: 
Facets
Depth (avg): 
2'
Depth Range: 
12" to
3'
Width: 
100'
Vertical: 
200'
People Involved
Caught: 
1
Carried: 
1
Snow Profile
Snow Profile Comments: 

Faceted snow near ground

IMG_1637.JPG
General Comments

Very experienced but fairly large party triggered 2 avalanches on adjacent slopes.   One person caught and carried in second av

IMG_1650.JPG
General Comments 2

Rider was ascending a skin track on a split board when avalanche released above him...The avalanche caught the tails of his boards and engulfed him, but he was able to grab hold of a stump in the descent and hold on while the bulk of the moving snow rolled past him...

"The 3rd pic is the one that carried me, you can see my pole at the top log where it swept me in by the tails of my boards.  I grabbed the log and it pulled me away.  I also grabbed at the lower debris as it passed with little success to hold on.  It did slow me down enough to slide out to the edge.  My other pole was at the bottom on top of the debris pile."

P1210120.jpg
General Comments 3

The party decided to ascend the path of the first avalanche, which became problematic....

P1210116.jpg
General Comments 4

Here's a view of the crown and bed surface of one of the two avalanches....

P1210119.jpg
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