Mehcanical, Chemical and Biological weathering 

HideShow resource information
View mindmap
  • Weathering
    • Mechanical
      • the breakdown of rocks without changing its chemical composition
      • Freeze-thaw weathering
        • 1) water gets into cracks in rocks
        • 2) when water freezes it expands, puts pressure on rock
        • 3) when water thaws it contracts, releases pressure
        • 4) repeated freezing and thawing, widens cracks and causes rock to break up
      • Onion skin weathering
        • Exfoliation: outer layer of rock flakes away from the rest
        • happens due to very hot weather
        • as rock repeatedly expands and contracts, causes outer layer of rock to peel away
    • the decay or disintegration of rocks from their original place
    • Chemical
      • the breakdown of rock by changing its chemical composition
      • Carbonation weathering
        • 1) rain has carbon dioxide in it, makes a weak carbonic acid
        • 2) carbonic acid reacts with rock that contains calcium carbonate. Rocks are dissolved by the rainwater
    • Biological
      • the breakdown of rocks by plants (tree roots) and animals


No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Coastal zones resources »