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An accumulation of till at the terminus or snout of a glacier.
End moraines in alpine areas tend to form ridges, but the actual size and appearance of the ridges may vary considerably depending
on the amount of time during which the glacier margin was stationary, the amount of material the glacier was transporting, and the
rate of ice flow. If the glacier margin is stationary (i.e. the size of the glacier does not change) for a long time period, a
large moraine (ridge) may form. If the glacier margin was stationary for just a year or several months, a well-defined ridge may
not form. Glaciers transporting large amounts of sediment are more likely to form large end moraines (ridges) compared to glaciers
transporting only small amounts of sediment, all other factors being equal. Glaciers with fast flow rates are more likely to form large end moraines (ridges) than
glaciers with slow flow rates, all other factors being equal.
End moraines in alpine areas generally stretch across the valley (from one side of the valley to the other side of the valley) and
may curve slightly downhill in the center due to the faster ice flow in the center of the glacier compared to ice flow along the
margins of the glacier. Two different types of end moraines are terminal moraines and recessional moraines. The terminal moraine
marks the farthest extent of glacial advance and thus is located at the lowest elevation. Recessional moraines form when glaciers
are temporarily stationary during periods of overall glacial retreat and thus are located at higher elevations than the terminal
moraine. After glaciers retreat, these end moraines may be greatly modified or destroyed by subsequent fluvial erosion.
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