(a) State the difference between erosion and mass movement (b) List four agents responsible for modifying landforms (c) Outline three factors that influence...

Answer Details

(a) Difference between erosion and mass movement

Erosion is the wearing away and removal (transportation) of weathered rock and soil from one place to another by an active agent such as running water, wind, ice or waves. Mass movement (mass wasting) is the downslope movement of rock waste and soil mainly under the direct pull of gravity, without the necessary aid of a transporting agent. In short, erosion needs a moving agent and carries material far away, while mass movement is gravity-driven and usually moves material a shorter distance down a slope.

(b) Four agents responsible for modifying landforms

• Running water (rivers).
• Wind.
• Moving ice (glaciers).
• Sea waves (marine action).

(Underground water is also acceptable.)

(c) Three factors that influence mass movement

• Gradient (steepness) of the slope: the steeper the slope, the faster and more likely the movement.
• Amount of water in the material: water adds weight and lubricates particles, reducing friction and triggering flows and slides.
• Nature of the rock/soil and vegetation cover: loose, unconsolidated material with little vegetation to bind it moves more easily than solid, well-vegetated ground.

Other valid points: earthquakes/vibrations, human activities (mining, road cutting).