Glacial Erosion

Glacial erosion is the process by which glaciers, massive bodies of ice, carve and shape the land through the action of ice, water, and sediment. Glaciers have the capacity to erode the earth's surface through a variety of mechanisms, including plucking, abrasion, and glacial meltwater erosion.

Mechanisms of Glacial Erosion

1. Plucking: This occurs when a glacier picks up rocks and sediment as it moves over the landscape. As the ice melts and refreezes, it can "pluck" or remove rocks from the bedrock.
2. Abrasion: Glacial ice contains sediment that acts like sandpaper, grinding and scraping against the underlying rock, wearing it down over time.
3. Glacial Meltwater Erosion: As glaciers melt, the water they release can create channels and valleys, carrying and depositing sediment as it flows, further shaping the landscape.

Landforms Created by Glacial Erosion

Glacial erosion can create a variety of distinct landforms, including:

• U-shaped valleys: These valleys have steep, straight sides and flat bottoms, carved out by the movement of glaciers.
• Arêtes and horns: These are sharp, rugged features formed by the erosion of cirque glaciers on a mountain.
• Glacial troughs: These are deep, long valleys carved out by glaciers as they move down a mountain.
• Fjords: Fjords are long, narrow inlets with steep sides or cliffs, created by glacial erosion and subsequent inundation by the sea.

Study Guide Questions

1. What are the main mechanisms of glacial erosion?
2. How do U-shaped valleys differ from V-shaped valleys?
3. Explain the process of plucking and its role in glacial erosion.
4. What landforms are created by glacial erosion?
5. Describe how glacial meltwater erosion contributes to shaping the landscape.

Studying glacial erosion provides fascinating insights into the transformative power of glaciers and their role in shaping the Earth's surface over geological time.