2.6A Weathering

• Physical weathering = application of force to physically fragment rock into smaller pieces called clasts.

  • It breaks down rocks by the exertion of a physical force, and does not involve any chemical change. 
  • e.g. Freeze-thaw affect and salt-crystal growth
• chemical weathering = Where chemical reactions attack individual minerals in the rock, breaking bonds and producing new chemical compounds. 

  • e.g. oxidation and hydrolysis
• biological weathering = the break down of rock in situ by living or once-living organisms.

  • e.g. tree-root weathering and seaweed acid
• weathering impacting rate of recession by:

  • weakens rocks, making them more vulnerable to mass movement and cliff retreat
  • A hot, wet climate encourages chemical and biological weathering