rock flour
Quick Summary
Rock flour, also known as glacial meal, is finely powdered rock material created by the grinding action of glaciers on their beds. This fine sediment, often colloidal in size (less than one micrometer in diameter), is a significant component of glacier streams. The suspended rock flour can persist for great distances and is responsible for the distinctive green color observed in many Alpine lakes. Glaciers are powerful agents of erosion, producing sediment at rates typically around one millimeter per year, with higher rates in steeper or softer bedrock areas.12
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glacial landformRock polish…a glacier is the so-called rock flour produced by the constant grinding at the base of the ice. Rock flour acts like jewelers’ rouge and produces microscopic scratches, which with time smooth and polish rock surfaces, often to a high lustre.
Read More…a glacier is the so-called rock flour produced by the constant grinding at the base of the ice. Rock flour acts like jewelers’ rouge and produces microscopic scratches, which with time smooth and polish rock surfaces, often to a high lustre.
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glacierGlacier hydrology…a distinctive fine-grained material called rock flour, or glacier flour, which is colloidal in size (often less than one micrometre in diameter). The suspended sediment concentration decreases with distance from the glacier, but the rock-flour component may persist for great distances and remain suspended in lakes for many years; it…
Read More…a distinctive fine-grained material called rock flour, or glacier flour, which is colloidal in size (often less than one micrometre in diameter). The suspended sediment concentration decreases with distance from the glacier, but the rock-flour component may persist for great distances and remain suspended in lakes for many years; it…
Read More