Toured up Beartrap West, down the mellow ridge to Desolation Lake, and over to Powder Park 1. Saw numerous old avalanches on steep shaded north facing terrain. The slab avalanche on the northeast facing terrain at Desolation Lake has not been reported. I do not know when the avalanche occured but I guess it was remote triggered by ski tracks nearby sometime between Sat Dec 18 and Sun Dec 19th. Slab looked about 1.5 feet thick and ran various lengths (hard to tell since I didn't want to get too close) between the trees towards Desolation Lake. Cracks propagated at least 200 feet beyond the avalanche down the ridge into less steep terrain.