Coastal erosion Flashcards
What is Abrasion?
When waves advance they pick up sand and pebbles from the seabed then when they break at the base of the cliff the material is hurled at the foot of the cliff chipping away at the rock
What is Hydraulic action?
When a wave advances air can be trapped and compressed either in the joints of the cliff or between the breaking wave and the cliff, then when the wave retreats the compressed air expands and this continuous process can weaken joints in the cliff causing pieces to break off
What is Corrosion?
When cliffs are formed from an alkaline rock such as chalk or limestone they can be slowly dissolved by weak acids in the seawater
What are some examples of landforms caused by coastal erosion?
Headlands and bays, cliffs, stacks and stumps, shoreline platforms
How are wave cut notches created?
They are a result of waves breaking against the foot of a cliff eroding the rock through either abrasion, hydraulic action or corrosion
How can a wave cut notch result in the cliff collapsing?
As the wave cut notch enlarges undercutting the cliff the rock above it becomes unstable and eventually collapses
How is a shoreline platform created and how does it affect further erosion?
As a wave cut notch migrates inland and the cliff retreats remnants are left behind, this is called a shoreline platform causing waves to break earlier limiting further erosion of the cliff
What is the process of caves, arches, stacks and stumps?
Waves erode joints and cracks in the cliff to create caves which are then made larger until an arch is formed, this arch then collapses to leave a stack and the stack is further eroded to leave a stump (Detail in TB)
