Flashcards in 3 Physical Landscapes (coastal keywords) Deck (26):
Movement of a wave into the beach.
Movement of a wave back into the sea.
The top of the wave.
The back of a wave.
The vertical distance from trough to crest.
The horizontal distance between two crests.
The number of waves breaking per minute.
Water gets into the cracks and joints in the rock, and as it freezes, the volume expands. This puts pressure on the surrounding rock and the crack is widened.
This is called ‘freeze-thaw action’. Over time the size of the crack increases, until a block of rock breaks off.
This occurs when water reacts with the calcium carbonate in rocks like limestone and chalk. The calcium carbonate dissolved and is washed away in solution, weakening the rock.
Due to the actions of flora and fauna. Plant roots grown in cracks in the rocks. Animals suck as rabbits burrow into weak rocks.
This is when large chunks of rock slide down the slope quickly without any warning.
This is common when the cliffs are made of clay. The clay becomes saturated (soaked with water) during heavy rainfall and oozes down towards the sea.
Fragments of rock break away from the cliff face.
Coastlines where the geology alternates between bands of hard rock and soft rock.
When a Coastline has the same type of rock along its length.
Working with nature to help maintain the present coastline.
Man-made structures built to ensure total protection of the present coastline.
Do nothing and allow present coastline to change.
A concrete wall designed to reflect the waves back out to sea and/or absorb their energy. Sometimes has a promenade built on it.
A wooden or stone groyne is built in the beach at right angles to the coast they stop long shore drift by trapping sediment, building up the beach.
Big boulders places at the base of the cliff - dissipate the energy of the waves.
Steel wire mesh cages filled with pebbles or rock at the back of the beach to create a low wall-like structure. Cages absorb some of the energy.
Replacement of lost sediment. A nourished beach means fewer waves reach the bank of the beach. As more wave energy is absorbed and dissipated by the beach, the rate of erosion is reduced.
Artificial reshaping of a beach using existing material. Beach is lowered in winter destructive waves. After storms, bulldozers move shingle back up the beach. This ensures the beach is large enough to be an effective buffer.
Artificial creation of new sand dunes or restoration of existing dunes. Physical barrier between sea and land.