A glacial lake in Chile's southern Andes has disappeared - and scientists want to know why. The disappearance of the two-hectare lake in Bernardo O'Higgins National Park was discovered in late May by park rangers. Where the lake had been in March, they found a dry crater 30-meters deep and several large pieces of ice that used to float atop the water. "The lake had simply disappeared," Juan Jose Romero, head of Chile's National Forest Service in the southernmost region of Magallanes, said Wednesday. "No one knows what happened." Romero said that a group of geologists and other experts would be sent to the area 2,000 kilometers southeast of Santiago in the next few days to investigate. One theory is the water disappeared through cracks in the lake bottom into underground fissures. But experts do not know why the cracks would have appeared because there have been no earthquakes reported in the area recently, Romero said. A river that flowed out of the lake was reduced to a trickle.