| Term: | striations |
| Definition: |
Linear fine scratches formed by the abrasive effect of debris-rich ice sliding over bedrock. Intersecting sets of striae are formed as stones are rotated, or if the direction of flow over bedrock changes. Or Striae Swisseduc
Easily recognizable convex growth feature across facets or crystal surfaces. IACSSnow Striations are the scratches etched into the rock at the bed of a glacier. Their presence indicates grinding of sand and rock particles into the bed under considerable pressure. Glacier ice alone is too soft to be a powerful rock-cutting agent. Many glaciers are armed with rock fragments embedded within the ice that are effective cutting tools. The rock-choked ice grazes over the glacier bed, removign rock obstacles and leaving the bedrock rounded and smoothed. In some places fine-grained debris polishes the bedrock to a lustrous surface finish called glacial polish. Coarser rocks may gouge scratches called striations. Multiple, generally parallel, linear grooves, carved by rocks frozen in the bed of a glacier into the bedrock over which it flows. Grooves of scratches found in surface rock that are the result of glacial abrasion. PhysicalGeography GCW |