The layer at 110 was breaking, but I could not isolate the grain type responsible for this. This is the only pit with this instability. I am thinking it is an isolated weakness.
Profile from shallow side of AMu-HS-R4-D3-G.Triggered 1/4/20. Very large, 800-1000' wide, 120-150' vertical, 4-10' deep hard slab, knife hard where crown was deepest.