Crevasse
deep crack, or fracture, found in an ice sheet or glacier From Wikipedia, the free encyclopedia
A crevasse is a deep crack, or fracture, found in an ice sheet or glacier. It is like a crevice that forms in rock. Crevasses form as a result of the movement caused by the shear stress between two semi-rigid pieces of ice.

Crevasses often have vertical or near-vertical walls, which can then melt and create seracs, arches, and other ice formations.[1]
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