Chemical Processses

• Carbonation


  Rainwater picks up CO2 to form a weak carbonic acid

  Water infiltrating into the soil picks up more CO2 from the soil air

  Weak carbonic acid can dissolve carbonate minerals

  Limestone is most susceptible to this
• Hydrolysis


  Silicate minerals react with H+ Ions from water

  Clay minerals and ions are produced

  Quartz is unreactive

  Feldspar is very susceptible
• Oxidation


  Ability for minerals to incorporate oxygen atoms into their atomic structure

  Affects iron rich minerals most readily

  Results in a red/brown colouration
• Spheroidal Weathering


  Rectangular blocks outlined by joints undergo chemical weathering

  Corner and edges weather more readily

  Once spherixal no more weathering takes place