Sunday, 4 May 2008

Coastal erosion processes

You need to be able to define the four main processes of coastal erosion.

Corrasion (abrasion) - this is where the bits of rock and sand carried in the waves grind down cliffs.

Attrition - this is where the waves cause rocks and pebbles that they are carrying to smash into each other and break down. They become smaller and rounder.

Solution - this is where acids contained in sea water slowly dissolve certain types of rock.

Hydraulic Action - this is the constant force of waves crashing on the shore. When waves crash against the cliffs they force air into cracks in the rock. The air is trapped, and pressure builds up. As the waves move back, pressure is released and the trapped air expands. Small explosions take place and weaken the rock.

You might find it useful to remember the 4 processes using the phrase CASH.

The BBC Bitesize website has a useful animation showing these four processes. Click here to visit this page.

Remember the Coastal Kung Fu from our lessons? This activity was designed by Portchy from SLN. Thanks! Click on the image to re-live the experience.

1 comment:

LJT_our learning journey said...

Thank you, this is very helpful! :)