Vertical erosion in the upper course deepens the bed and makes the valley sides unstable, sometimes collapsing to create which type of valley?

Vertical erosion in the upper course deepens the bed and makes the valley sides unstable, sometimes collapsing to create which type of valley?

• A. Upper course
• B. V shaped valley
• C. Waterfalls
• D. Tributary

Answer: (B)

Vertical erosion in the upper course carves down into the bedrock, deepening the channel much faster than it widens it. This creates a deep, narrow valley with steep, almost vertical sides. As the valley walls become unstable due to weathering and mass wasting, sections can collapse, further sharpening the sides. The cross-section of such a valley resembles a “V,” which is why this shape is characteristic of the upper course. While waterfalls can occur here due to variations in rock resistance, they describe features along the valley rather than the valley’s overall shape, and a tributary is simply a smaller stream joining a larger one.

Vertical erosion in the upper course carves down into the bedrock, deepening the channel much faster than it widens it. This creates a deep, narrow valley with steep, almost vertical sides. As the valley walls become unstable due to weathering and mass wasting, sections can collapse, further sharpening the sides. The cross-section of such a valley resembles a “V,” which is why this shape is characteristic of the upper course. While waterfalls can occur here due to variations in rock resistance, they describe features along the valley rather than the valley’s overall shape, and a tributary is simply a smaller stream joining a larger one.