Erosion and deposition

• What is the key question addressed in Unit 2 on erosion and deposition?

  What are the features of erosion and deposition associated with rivers, sea, glaciers, and wind?
• What is the main difference between weathering, erosion, and deposition?

  Weathering breaks down materials, erosion moves them, and deposition places them in new locations.
• What are the key terms associated with erosion and deposition?

  • Attrition
  • Corrasion
  • Deposition
  • Erosion
  • Sediments
  • Elevations
• What is the definition of sediments?

  Materials that settle to the bottom of a liquid.
• What are the five agents of erosion and deposition?

  Gravity, water (rivers), glaciers, sea waves, and wind.
• How does gravity contribute to erosion?

  Gravity causes mass-wasting, moving materials from higher to lower elevations.
• What are the three stages of a river course?

  1. Youth
  2. Maturity
  3. Old age
• What characterizes the youth stage of a river?

  The river flows quickly, has waterfalls, and features rapid vertical erosion.
• What type of valley is formed during the youth stage of a river?


  1. shaped valleys.
• What characterizes mature rivers?

  Mature rivers have a wide valley floor, more lateral erosion, and meanders.
• What is hydraulic action in the context of wave action?

  Hydraulic action is the force of water on cliffs or coastal rocks that breaks them apart.
• What are spits and barrier islands formed by?

  Deposition associated with wave action.
• How do beaches form?

  Beaches form when rivers carry sand from erosion to the shore, where it is deposited.
• What processes cause erosion by moving ice?

  Abrasion and plucking.
• What are the features of glacier erosion?

  Horns, arêtes, and cirques.
• What is till in the context of glacial deposition?

  Till is boulder clay or other sediments deposited by a glacier.
• What is the difference between terminal moraine and recessional moraine?

  Terminal moraine is deposited at the furthest advance of a glacier, while recessional moraine is deposited when a glacier retreats.
• What is the impact of wind on erosion?

  Wind can erode, transport, and deposit material, especially when picking up sand particles.
• What are the two important processes in wind erosion?

  Abrasion and deflation.
• What is the effect of soil compaction caused by farm animals?

  It makes it difficult for plants to grow and for soil to absorb water.
• How does construction contribute to erosion?

  Construction uproots vegetation, alters drainage patterns, and compacts soil.
• What are the two types of mining that cause erosion?

  Open-cast (strip) mining and underground mining.
• What happens during open-cast mining?

  Earth and rocks are scraped away to access minerals near the surface.
• How does underground mining contribute to erosion?

  It can collapse and create depressions that collect water, causing erosion.
• What are the main human activities that contribute to erosion?

  • Agriculture
  • Construction
  • Mining
• What are the consequences of soil compaction?

  • Difficult for plants to grow
  • Reduced water absorption
  • Increased erosion risk
• What are the effects of deforestation on soil erosion?

  • Increases water flow rate
  • Exposes soil to wind and rain
  • Reduces vegetation cover