Glacier

Persistent body of ice that moves downhill under its own weight

A glacier (US: ; UK: or) is a persistent body of natural ice, a form of rock, that is constantly moving under its own weight. A glacier forms where the accumulation of snow exceeds its ablation over many years, often centuries. It slowly flows and deforms under stresses induced by gravity, undergoing both ductile and brittle deformation, and acquiring distinguishing surface features, such as crevasses and seracs.

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