Matier NW face

We triggered a shallow but quite large (size 1.5 to 2) soft wind-slab near the top of the NW face. It propagated across half the face with the 1st skier and more of that slab on the other side of the face went again with the 2nd skier. We noticed several similar wind slabs on other peaks at similar elevation and N aspect (Slalock, Joffres). The snow on the E side of Anniversary Glacier was also starting to form a soft slab