Avalanche: Thousand Turns Gulley

Observer Name
B
Observation Date
Saturday, December 14, 2019
Avalanche Date
Saturday, December 14, 2019
Region
Salt Lake » Big Cottonwood Canyon » Brighton Perimeter » Thousand Turns Gulley
Location Name or Route
Thousand Turns Gully/rider's left wall
Elevation
9,800'
Aspect
Northeast
Slope Angle
Unknown
Trigger
Skier
Trigger: additional info
Remotely Triggered
Avalanche Type
Soft Slab
Avalanche Problem
Wind Drifted Snow
Weak Layer
Density Change
Depth
10"
Width
175'
Vertical
250'
Comments
4 Turns down into the low angle 1000 Turn Gully run, the entire steep left wall was remotely triggered. It never came close to the triggering rider. It was a Wind Slab that was 8 to 10 inches deep, 1 Finger minus in Hardness, and had Graupel as the weak layer. The debris ran down through the choke of the gully and past the mid slope roll where it enters in the lower section below Figure 8 Bowl. Debris was shallow and spreading out, and was 18 inches deep at it's largest area of deposition. The entire slide consisted of multiple connected pockets with numerous areas that broke out below rocks and cliffs. Grauple Pooling appeared to help the propagation propencity. Upon descent in the bottom half of the run, it was easy to initiate long running cracks on the NW facing wall that is on the rider's right, but the slope angle (between 30 and 35 degrees) was not allowing it to move.
Unfortunately the poor visibility, Moderate to Strong Winds, Intense Wind Blown/Transport and safety considerations not only did not allow for good photos, but it also prevented any opportunities to examine yesterdays accident scene and slide on Figure 8 Hill. Reports from the Brighton Ski Patrol estimated that slide at 200 feet wide, 2 to 4 feet deep, and only in the new snow.
Annotation on photo 1 depicts 2/3's of the downhill length of the slide in the 1000 Turn Gully area. Photo 2 shows one section of the crown area.
Coordinates