Quartz (Pitch and Putt)

Large group did many snowboard laps on a more true north aspect of same slope with no signs of instability. At one point I had cracking on a very small NE facing convex feature that was obviously wind loaded. Two other members of the group went to snowmobile down the NE aspect above the climb and triggered the slab where it was thinnest (~30cm). It propagated roughly 100m down the ridgeline, the crown measuring up to 80cm in heavily loaded spots (average 50cm). The first sledder made it out of the way, the second got caught at the top of the ridge and rode down roughly 50m separated from his snowmobile, resulting in a full burial, 0.75-1m deep. No injuries sustained. His snowmobile was partially buried 30m further down slope in the debris. Up to 2.5m of debris in gully used as uptrack. Triggered on Feb 21 surface hoar.