Yellowstone Quake 'Swarm' Raises Disaster Fears

The "supervolcano" at Yellowstone National Park is being hit by a swarm of hundreds of earthquakes, according to researchers who have been tracking seismic activity this week. More than 400 have been detected in the area since June 12, including a 4.5 magnitude quake within the park on June 15. Researchers say the risk of activating&