| Term: | Glacial flour |
| Definition: | Glacial flour is the fine-grained sediment carried by glacial rivers that results from the abrasion of rock at the glacier bed. Its presence turns lake water aqua blue or brown, depending on its parent rock type. Rivers originating beneath glaciers are choked with glacial flour, the silty fine-grained sediment produced by the abrasion of rocks at the glacier bed. |