Rutschblock Test on Andesite Ridge

Location Name: 
Andesite Ridge
Region: 
Donner Summit Area
Date and time of observation: 
Sun, 01/10/2016 - 11:00
Location Map: 
United States
39° 20' 59.9604" N, 120° 21' 45.3816" W
US


Red Flags: 
Obvious avalanche path
Terrain Trap

Observation made by: Guide at Tahoe Mountain School
Snowpit Observations
More detailed information about the snowpack: 

Both the Jan. 5th buried surface hoar (now about 40cms down in this location) and the Jan. 9th buried surface hoar (now about 3 cms down) were widely observed on open areas in north facing near treeline terrain on Andesite today. In additon to sudden collapse compression test results, ECTs that propogated, we also performed a Rutschblock test (video) that failed on RB 4 with whole block failure on the 1/5 surface hoar layer.

PSTs on the 1/5 layer in this pit produced 77/100 End and 80/100 End results. Pits close by but in slighly more treed locations resulted in CTs with sudden collapse but did not yield ECTs that propogated.  

 

Snowpit videos (tests, etc): 

RB 4 2016.1.10 on Andesite Ridge