Freeze thaw- water enters a crack then freezes in cold weather. Once froze it expands in volume by 10%. This exerts pressure on the rock and with repeated occurrences the fragments break away.
Salt crystalisation- once salt evaporates it leaves salt behind, these salts can grow and exert stress into the rock
Wetting and drying- frequent cycles of wetting and drying on the coast; rocks rich in clay expand when wet and contract when dry and break
Biological weathering- thin plants grow into cracks in a cliff face and these rootswiden and break up the rock
