Avalanches

Avalanches occur as rapid, gravity-driven accelerations of different materials downslope at high rates of speed. All avalanches are caused by an overburden of material that is too massive and unstable for the slope that supports them. At least five different types occur, each type with numerous subtypes or relationships to other types: (1) snow avalanches, (2) ice avalanches, (3) slush avalanches, (4) debris avalanches, and (5) rock avalanches. Because of their common high velocities, all avalanches are greatly threatening to life, limb, and property, and the lives of tens of thousands of people have been lost in the many notorious occurrences. Because of the steep slopes and high potential energies of mountains that can convert their potential energy into high kinetic energy wherever snow, ice, ...