Stack (geology)

Geological landform consisting of a steep and often vertical column or columns of rock

A stack or sea stack is a coastal geological landform consisting of a steep and often vertical column or columns of rock in the sea near a coast, formed by wave erosion. Stacks are formed over time by wind and water, processes of coastal geomorphology. Stacks form when a headland is progressively eroded by hydraulic action and abrasion.

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