Solution or carbonation weathering
The limestone solution process is also known as carbonation.
- Limestone is made of calcium carbonate. When carbon dioxide is dissolved in rainwater, it makes a weak acid called carbonic acid.
- When carbonic acid comes into contact with limestone and passes through joints and bedding planes, it reacts with the rock to form calcium bicarbonate.
- The calcium bicarbonate is soluble and is carried away in solution, gradually weathering the limestone.