Chemical weathering

Chemical weathering

1. oxidation

   • some minerials of a rock are destroyed by oxidation
   • oxidation of metals is a well-known form this type of weathering
   • iron becomes iron oxide (rust) which is easy to break
   • most of the rocks contain different metals
   • the process of oxidation makes rocks more and more instable

2. acid action

   • solution is the most important process
   • acid water can react with minerals of a rock, some minerals are washed away
   • the intensity depends on the temperature and the acidity
   • hot temperatures and enough water as in tropical regions help to dissolve minerals

3. dissolution of limestone

   • CO² can be dissolved in water
   • Carbonic acid (H² CO³) can dissolve limestone
   • water temperature and pressure influrence this process