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Why do glaciated mountain regions often have sharp peaks and steep-sided valleys?

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esker: Nunavut — glacial landform Eskers, or narrow ridges of gravel and sand left by a retreating glacier, wind through western Nunavut, Canada, near the Thelon River.

Glaciated mountain regions develop their characteristic sharp peaks and steep-sided valleys through intense glacial erosion and physical weathering processes.

Steep-Sided Valleys

Glaciers reshape V-shaped stream valleys into U-shaped valleys by removing loose debris and aggressively eroding the bedrock along the valley floor and lower sidewalls. Unlike rivers, which erode a narrow line, glaciers occupy a large portion of the valley's cross-section, effectively widening and deepening the trough while creating steep, often vertical walls.12

Sharp Peaks and Ridges

The formation of jagged features is driven by the following processes:
* Arêtes: As glaciers erode parallel valleys, the bedrock divides between them are narrowed into sharp, knife-edge ridges known as arêtes.1
* Horns: When three or more cirques erode radially into a mountain, they leave behind a sharp, pyramid-shaped peak called a horn, such as the Matterhorn.13
* Frost Shattering: High peaks are further sculpted by freeze-thaw activity, where water freezing in rock cracks exerts immense pressure, causing the rock to fracture and retreat.145