Arkansas -- Mystery Quakes

Something weird has been shaking the small town of Guy, Arkansas. Last September, the tiny community just north of Little Rock experienced nearly 500 earthquakes in just a few weeks' time, including 15 quakes in one day. Officials from the U.S. Geological Survey say the quakes are happening less than a mile below the town. The theory that a local gravel company's operations were to blame was quickly discounted, leaving no explanation for the tremors.