Geologists Jon Major and Ed Wolfe view an unusual flowing mixture of water and ice in the upper Drift River. The flow was produced by a sudden release of impounded water from the upper reaches of the Drift River canyon which drains the summit crater of Redoubt Volcano. Photograph by G. McGimsey, U.S. Geological Survey, March 15, 1990.
Image courtesy of AVO / U.S. Geological Survey.