Examkin

Question

Difficulty: EasyLandform Development by Wind Action and Glaciation

In arid regions, wind action causes severe erosion through different mechanics. Which landform is created when wind abrasion selectively undercuts the base of a rock outcrop more rapidly than its top due to sand particles being carried close to the ground?

  1. Mushroom rockAnswer
  2. B
    Oxbow lake
  3. C
    Scree slope
  4. D
    Delta

Answer

Mushroom rock (also known as a pedestal rock)
Wind abrasion in deserts is most effective close to the ground where wind-borne sand particles are concentrated. When an isolated rock mass is exposed to this sandblasting action, the lower portion erodes significantly faster than the upper part, creating a distinctive mushroom rock (pedestal rock).

Step-by-Step Solution

1
Identify the primary agent and mechanism described in the question
The agent is wind (aeolian process) using wind abrasion (sandblasting action near ground level).
Wind action carries the heaviest abrasive tools (sand grains) close to the surface, typically within 1 to 1.5 meters above the ground.
2
Analyze the structural outcome of ground-level undercutting on an isolated rock
The base of the rock undergoes maximum erosion while the top remains wider and less eroded.
Differential erosion leaves a narrow stalk supporting a wider cap rock, forming a pedestal or mushroom shape.

Key Concept

Aeolian Abrasion and Landform Development
Rate this question

Topics

Landform Development by Wind Action and Glaciation

More questions from this topic