Question

Which landform is created by the erosional work of a glacier?

• A. Delta
• B. U-shaped Valley
• C. Sand Dune
• D. Flood Plain

Hint:

A simple way to remember: \textbf{River erosion $\rightarrow$ V-shaped valleys} \textbf{Glacial erosion $\rightarrow$ U-shaped valleys} If you see a \textbf{broad valley with steep sides and a flat floor}, it is most likely a \textbf{glacially formed U-shaped valley}.

Answer 1

The Correct Option is B

Concept: Glaciers are large masses of ice that move slowly over land due to gravity. As they move, they erode the underlying rocks through processes such as plucking and abrasion. These erosional processes carve distinctive landforms on the Earth's surface. Major erosional landforms formed by glaciers include:

• U-shaped valleys
• Cirques
• Arêtes
• Horns

Among these, the U-shaped valley is the most common and characteristic feature produced by glacial erosion. Glaciers widen and deepen pre-existing river valleys. Rivers usually create V-shaped valleys, but when glaciers pass through these valleys, their immense weight and slow movement reshape them into broad, flat-bottomed valleys with steep sides, forming a U-shaped cross-section. Thus, a U-shaped valley clearly indicates that the landform was shaped by glacial erosion.
Step 1: Understanding glacial erosion.
When glaciers move downhill, they erode rock surfaces by:

• Plucking: Ice freezes into rock cracks and pulls pieces of rock away.
• Abrasion: Rocks embedded in the glacier scrape and grind the valley floor and sides.

These processes significantly reshape the landscape.
Step 2: Identifying the landform produced by glaciers.
Due to intense erosion, glaciers convert narrow V-shaped river valleys into wide U-shaped valleys. These valleys have:

• A flat or gently rounded valley floor
• Steep valley sides
• A broad U-shaped cross section

Hence, the landform produced by glacial erosion is a U-shaped valley.
Step 3: Eliminating incorrect options.

• Delta: Formed by deposition of sediments by rivers at their mouths.
• Sand Dune: Formed by the depositional work of wind in desert regions.
• Flood Plain: Created by river deposition during floods.

None of these landforms are formed by glacial erosion.