With a wind and ice crust from warm temps and some rain, the new and wind blown snow was very reactive in the 9500'- 9900' range on the Park City ridge line. We first approached a steeper couloir just below 10,000' and remote triggered a cornice. As we worked our way around the skiers left I skied over 2-3" of new, wind blown snow. That bit of snow broke out and a bit to my surprise because of the lack of snow, it propagated up the ridge where there was more snow and a bit of a cornice. Just above me, there was probably only an inch of new snow, but my trigger was enough to propagate through that 1" of snow where there was wind blown snow of more than 12". Because of the slippery/icy surface, the snow picked up significant speed. It was enough, coupled with some exposed rocks and a cliff a couple hundred feet below that a ride would have been nasty to say the least. Most of the bowl broke out and from top to bottom the slide was 400-500'. I've attached a photo of the lower portion of the lower slide from below and a video of the remote trigger of the cornice fall.