Avalanched on while ice climbing in prominent ice-filled gulley just east of the Y-Couloir. Avalanche occurred while on last pitch of climb. There was a soloist somewhere above who was trying to link this climb with the Y-Couloir who may have triggered the slide. It was only by luck that my partner and I were each at an anchor (top and bottom of pitch) when the slide came down, otherwise we would have been carried.
Occurred in ice gulley farthest right in the photo. Looking back up at it from the road, one would not think that there was enough snow in the area to avalanche. There must have been a wind loaded pocket somewhere above, on top of our rotten base, that clearly was able to gain momentum as it got funneled down the gulley.
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Weak layer and depth given above are a best guess.