Aspen
AvalancheAnonymous · Dec 14, 2020 · Aspen
Weather
Snowing moderately, calm winds, ~20 degrees F. ENE 10400', Marble Point.
Snowpack
Roughly 2' storm slab atop consolidated older snow. Very poor adhesion at the interface. Widespread whompfing and shooting cracks noted on a similar aspect and slope angle at roughly 11,000' elevation. Did not quantitatively examine the crystal structure/habits at the interface of the slab.
Avalanche
Skier triggered an avalanche in a very small, localized gully atop a convexity adjacent to a small group of trees. The trigger point was the most thin area of the crown of the avalanche. Our group's travels were masked by complacency as we traversed low angle slopes on the return to the car after having noted major instabilities at higher elevations. The terrain immediately preceding the had such a gentle slope angle, and a significant enough amount of snow, that it was not possible to maintain one's momentum across it. We neglected to note and actively avoid steeper slopes, particularly areas of locally increased slope angles in small contours of the drainage. We took a moment to regroup next to the small grouping of trees , and plan our path towards the approach route in the trees farther to our left. We did not think much of the consequences of the shorter, but maybe 15 degree steeper slope below us that we would traverse across briefly; as my partner began to edge across the slope, it released and he was carried in a small avalanche that propagated roughly 100 feet wide and ran approximately 200'. My partner was carried, and briefly submerged in the moving snow before coming to rest atop the snowpack 100 or so feet above the toe of the slide. The event took place in a small contour to the drainage that became a terrain trap, and could have potentially resulted in an unnervingly deep burial. This slide was a sharp reminder of the potential consequences of any backcountry terrain, even in the relatively benign areas that we traverse on approaches to and exits from the main ski runs. We noted that we were in the place at the particular time as a result of having to conceded to the avalanche danger the possibility of skiing anymore that day. The decision to bail and cross very low angle terrain (up until the avalanche's path) in some ways made us un-perceptive to the hazards posed by the smaller undulations in the terrain that was below us. This served as a good reminder to ensure that my companion rescue skills are practiced and efficient, and to carefully assess all terrain that we pass through throughout the season.