Drumlin Drumlin A drumlin, from the Irish word "droimnín" ("littlest ridge"), first recorded in 1833, and in the classical sense is an elongated hill in the shape of an inverted spoon or half-buried egg formed by glacial ice acting on underlying unconsolidated till or ground moraine. Drumlins occur in various shapes and sizes, including symmetrical (about the long axis), spindle, parabolic forms, together with transverse asymmetrical forms; their long axis is parallel to the direction of movement of the formative flow at the time of formation. Drumlins are typically long, less than high and between wide. Drumlins generally have a length:width
Glacial striation provide the abrasive power to cut trough-like "glacial grooves". Finer sediments also in the base of the moving glacier further scour and polish the bedrock surface, forming a "glacial pavement". Ice itself is not a hard enough material to change the shape of rock but because the ice has rock embedded in the basal surface it can effectively abrade the bedrock. Most glacial striations were exposed by the retreat of glaciers since the Last Glacial Maximum or the more recent Little Ice Age. As well as indicating the direction of flow of the glacial ice, the depth and extent of