Potential catastrophic flooding from landslide-dammed lakes, Glacier National Park, Montana, USA
Butler DR, Malanson GP, Oelfke JG. 1991. Potential catastrophic flooding from landslide-dammed lakes, Glacier National Park, Montana, USA. Zeitschrift fur Geomorphologie NF
The Rocky Mountains have a high hazard potential from rapid slope failures, subsequent damming of drainage systems, and catastrophic rapid drainage of the landslide-dammed lake. Most landslide dams eventually fail by overtopping. This paper examines the history of, and the potential for catastrophic failure and high discharges from, a pair of landslide-dammed lakes in Glacier National Park, Montana, US. Tree-ring and lichen data from the surface and margins of the rockfall-avalanche dams indicate contemporaneous deposition occurred in 1910, with additional deposition in 1946. The rockfall-avalanche dams overlie Cretaceous shale capped with late Pleistocene glacial till. The deposits are therefore inherently unstable. The smaller of the two lakes undergoes dramatic fluctuations in lake level. Additional rockfall activity into the lakes is likely and could lead to catastrophic overtopping and dam failure.
- Type
- Journal Article
- Authors
- Butler, David; Malanson, George; Oelfke, Jack
- Units
- CRCO , GLAC
- Keywords
- Blackfeet Indian Reservation MT, Floods, Geologic Hazards, Lakes & Ponds, landslide dams, Physical Sciences