Surprise blast of rock, water and steam sends dozens running for safety in Yellowstone ABC NewsYellowstone Explosion Sends Park Visitors Fleeing The Weather ChannelVIDEO: Biscuit Basin geyser explodes, sending Yellowstone tourists packing Jackson Hole News&GuideHydrothermal explosion leads to closure of parts of Yellowstone National Park CNNBiscuit Basin in Yellowstone National Park temporarily closed due to hydrothermal explosion National Park Service