Poking around in hidden canyon, came across a cornice and what looked like a small wind slab nw facing 10000ft elevation Two riders in our party dropped around to the left . I went around to the far right side and triggered a wind slab breaking 1foot deep and 10 feet wide. I was carried about 6-7 feet down the slope towards a more wooded area of the slope and came to a hault. Not enough to bury someone but enough to take a unwanted ride. Mistakes where made and lessons were learned. We were glad there wasn't any serious consequences.