| Term: | Rock flour |
| Definition: |
Fine-grained, silt-size sediment formed by the mechanical erosion of bedrock at the base and sides of a glacier by moving ice. When it enters a stream, it turns the stream's color brown, gray, iridescent blue-green, or milky white. Also called Glacier Flour or Glacier Milk.
A fine powder of silt- and clay-sized particles that a glacier creates as its rock-laden ice scrapes over bedrock; usually flushed out in meltwater streams, causing water to look powdery gray; lakes and oceans that fill with glacier flour may develop a banded appearance. NSIDCCryosphere Very finely ground rock fragments that form between the base of a glacier and the underlying bedrock surface. PhysicalGeography GCW |