Medial moraine of Gornergletscher (Gorner Glacier) in the Pennine Alps near Zermatt, Switz.—Jerome Wyckoff

Accumulation of rock debris (till) carried or deposited by a glacier. The material may range in size from blocks or boulders to sand and clay, is unstratified when dropped by the glacier, and shows no sorting or bedding. Several kinds of moraines are recognized, depending on how they are deposited by the glacier; these include lateral moraines along the margins of the glacier and terminal moraines at its leading edge.

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