How do valley glaciers differ from continental ice sheets in the landforms they create?

Valley glaciers and continental ice sheets are both powerful agents of landscape change, though they differ primarily in their relationship to topography and the scale of the features they produce.1

Valley Glaciers

Valley glaciers are constrained by mountainous terrain, acting as rivers of ice that follow existing topography. They are defined by their erosional impact on mountain landscapes, where they carve V-shaped stream valleys into characteristic U-shaped valleys with steep, vertical sidewalls. Other distinct erosional features created by valley glaciers include:12
* Cirques: Amphitheatre-shaped hollows at the head of a glacier.2
* Arêtes: Sharp, knife-edge ridges separating parallel valleys.2
* Horns: Jagged mountain peaks formed by the intersection of multiple cirques.2
* Tarns: Lakes occupying basins scoured into the bedrock of cirques.2

Continental Ice Sheets

Continental ice sheets are massive, pancakelike bodies of ice that bury the underlying landscape, with flow directed outward from the center. While they share some depositional processes with valley glaciers, their features are often much larger in scale. Key landforms include:13
* Moraines: Large, laterally continuous ridges of till that mark the ice margin.3
* Drumlins: Streamlined, elongate mounds of sediment aligned with ice flow.3
* Eskers: Sinuous ridges formed by meltwater in subglacial tunnels.4
* Ground Moraine: A thin, hummocky sheet of till covering large areas.3

While outlet glaciers at the periphery of ice sheets can resemble valley glaciers, the primary distinction remains the ice sheet's ability to override and obscure regional relief.1