Coastal Landscapes

• How do waves form?

  Waves form by wind blowing over the sea and the friction causes ripples. the fetch is the distance the wind blows over.
• what happens when waves reach the coast?

  The wave breaks up as the seabed interrupts the circular movement of the water.
• draw the wave approaching the coast and explain it in order.

  1) circular orbit in open waters.

  
  

  2) friction with the seabed distorts the circular motion.

  
  

  3) the increasing eliptical orbit means the top moves faster. and the wave begins to break.

  
  

  4) On the seabed, water from the previous wave returns and water rushes up the beach.

  
• what are the two types of waves?

  constructive and destructive.
• draw a constructive wave

  
• draw a destructive wave

  
• what are the characteristics of constructive waves?

  lower height with longer wavelength, the waves spill forward and the swash is stronger than the backwash. this builds up the beach as it deposits sand/pebbles.
• what are the characteristics of destructive waves?

  higher waves with shorter wavelength, the waves break and plunge downwards and the backwash is stronger than the swash. this pulls the sand.
• what is weathering?

  the break down or dissolving of rocks and minerals on the surface of the earth.
• what is the difference between erosion and weathering

  erosion is caused by movement such as rivers. weathering is the breaking down of rocks.
• what are the 3 types of weathering?

  mechanical, chemical, biological
• what is chemical weathering?


  caused by chemical changes.
• what is physical/mechanical weathering?

  the disintegration and physical break up of rocks.
• what is biological weathering?

  break up due to plants and living things.
• what is an example of mechanical weathering?

  Freeze-thaw: in the day time water is collected in cracks, at night the water freezes and the expansion causes the cracks to enlarge. this repeated process causes rock fragments to break off and collect at the foot of the cliff.
• what is an example of chemical weathering?

  Carbonation, when there are chemical changes in rainwater, weak carbonic acid in rain water reacts with rocks such as limestone. the water becomes acidic by absorbing CO2. the rocks dissolve slowly.
• what is an example of biological weathering?

  Plant roots grow in cracks, animals such as rabbits can burrow into weak rocks (sand).
• what causes cliffs to collapse

  weathering which weakens rocks.
• what is mass movement?

  the downward movement of sliding material due to gravity.
• what are the 4 types of mass movement?

  Rockfall, landslide, mudflow, rotational slip
• with the aid of a diagram, explain rockfall

  due to freeze thaw, small parts of rock fall off the cliff face, causing scree at the bottom.

  
• with the aid of a diagram, explain mudflow


  soil filled with water and weak rocks can flow down the slope of a cliff in a stream.
• with the aid of a diagram, explain landslide

  bigger blocks of rock slide downhill.

  
• with the aid of a diagram, explain rotational slip

  a slump of saturated soil and weak rock along a curved surface.

  
• what is coastal erosion?

  the removal of material and the shaping of landforms.
• what are the 5 types of coastal erosion?

  solution, corrasion, abrasion, attrition, hydraulic power
• explain hydraulic power, with the aid of a diagram?

  power of waves as they smash onto a cliff. Trapped air is forced in cracks which lead so the rock breaking.
• explain abrasion, with the aid of a diagram?

  waves throw sediment in waves onto the rocks.
• explain attrition, with the aid of a diagram?

  sediment hits each other, this makes it smoother and smaller.
• explain corrasion, with the aid of a diagram?


  fragments of tock are carried in the water and is hurled at the cliff. The rocks scrape and gauge to erode the rock.
• explain solution, with the aid of a diagram?

  limestone cliffs dissolve the weak carbonic acid in sea water or rain.
• what are the 4 methods of transport? and what do they transport?

  solution

  suspension

  saltation

  traction

  
  

  all transport sediment.
• what is traction?


  large pebbles are rolled along the sea bed.
• what is saltation?

  rocks that bounce along the seabed
• what is solution?

  chemicals from chalk and limestone are dissolved in the water.
• what is suspension?

  particles suspended/carried in the water.
• what is longshore drift?

  the movement of sediment in a zigzag along the coastline.
• what is backwash


  sediment carried back down the beach as wave draws back.
• what is swash?

  waves carry sediment up the beach.
• explain longshore drift with a diagram

  1) the prevailing winds are responsible for the swash, the sediment approaches the coast at this angle and erodes the coastline.

  
  

  2) the backwash carries sediment back up the beach due to gravity.

  
  

  3) this moves the sediment along the beach and erodes the area.