Formation Sandur are found in glaciated areas, such as
Svalbard,
Kerguelen and
Iceland. Glaciers and icecaps contain large amounts of
silt and sediment, picked up as they
erode the underlying rocks as they move slowly downhill, and at the snout of the glacier, meltwater can carry this sediment away from the glacier and deposit it on a broad plain. The material in the outwash plain is often size-sorted by the water runoff of the melting glacier with the finest materials, like
silt, being the most distantly re-deposited, whereas larger boulders are the closest to the original terminus of the glacier.
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A load of sediment, consisting of sand and gravel, that is deposited by meltwater in front of a glacier.