Avalanche: Mineral Fork

Observer Name
Observation Date
Sunday, January 15, 2023
Avalanche Date
Sunday, January 15, 2023
Salt Lake » Big Cottonwood Canyon » Mineral Fork
Location Name or Route
Mineral Fork
Slope Angle
Avalanche Type
Soft Slab
Avalanche Problem
New Snow
Weak Layer
New Snow
We were a group of two skinning up towards the mid-elevation low-angle meadows of Highline. We were loosely following a burried but visible existing skin track. We came around a corner to find a small, steep, and relatively isolated slope under a rock band. The rocks were about 35 feet above us and the slope was 20 feet wide. After discussing options/precautions, skier 2 (submitter) stayed back in a safe spot while skier 1 stepped out into the slope. Skier 1's steps quickly triggered a slide in the new snow layer--roughly 6" on average and starting all the way from the rocks above. Skier 1 stayed in place on their feet during the slide then continued across to sub 30 degree terrain just beyond the slope.
The slide was 20 feet wide and went 200+ feet downhill. At it's deepest, the new snow layer there was 8" but was only 3" up at the rocks. The slope where skier 1 triggered it from was 39 degrees. At it's steepest by the rocks above, we would estimate the slope was nearly 45 degrees.
Overall the slide was small and the skier had no trouble standing in place while it happened. No movement at all in the 33 degree and 28 degree terrain over ridges on either side. However, we both immeadiately recognized that in larger terrain, the same situation could have been much worse. We double checked our plan and adjusted for extra caution.
Continued our day and saw no other red flags above this point. However, we were getting a lot of sluffing, cracking, and movement in the snow at much lower elevations on our way out.
It was a nice reminder that established skin tracks are not always the best option. On our way out we realized cutting over 250' lower in elevation would have completed avoided this terrain.