Bitesize has changed! We're updating subjects as fast as we can. Visit our new site to find Bitesize guides and clips - and tell us what you think!



When rock is exposed, there are a number of processes that break it down. Watch this video to find out more.


In order to see this content you need to have both Javascript enabled and Flash installed. Visit BBC Webwise for full instructions

Key points

  • Freeze thaw weathering is when water gets trapped in a crack or joint in the rock.
  • When the air temperature drops the water will freeze and expand. When the temperature rises, the ice melts.
  • If this process repeats, the rock will weaken and eventually shatter into angular fragments.
  • Limestone solution is where carbon dioxide dissolves in rainwater to make carbonic acid.
  • When this comes into contact with limestone, it reacts to form calcium bicarbonate. This is carried away in solution, gradually weathering the limestone.

All Geography videos

Rock landscapes and processes index

BBC © 2014 The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.