Key terms

• Chemical weathering - the breakdown of rock by chemical reactions with water, air or other substances.
• Erosion

  The breaking down or wearing away of substances in high energy areas.
• Transportation

  The movement of substances.
• Deposition

  The dropping of sediment in low energy environments
• • Hydraulic action - this is the sheer power of the waves as they smash against the cliff. Air becomes trapped in the cracks in the rock and causes the rock to break apart. This is called cavitation.
• • Abrasion - this is when pebbles grind along a rock platform, much like sandpaper. Over time the rock becomes smooth.
• • Attrition - this is when rocks that the sea is carrying knock against each other. They break apart to become smaller and more rounded.
• • Solution - this is when sea water dissolves certain types of rocks. In the UK, chalk and limestone cliffs are prone to this type of erosion.
• • the fetch - how far the wave has travelled
• Freeze-thaw weathering

  occurs when rocks are porous (contain holes) or permeable (allow water to pass through).
• Biological weathering

  Plants and animals can also have an effect on rocks. Roots burrow down, weakening the structure of the rock until it breaks away.
• Exposed rocks along the coastline can be broken down by the processes of weathering.
• Mass movement is the downhill movement of sediment that moves because of gravity.
• Rockfall

  Bits of rock fall off the cliff face, usually due to freeze-thaw weathering.

  
• Mudflow

  Saturated soil (soil filled with water) flows down a slope.

  
• Landslide

  Large blocks of rock slide downhill.

  
• Rotational slip

  Saturated soil slumps down a curved surface.

  
• • Solution - when minerals in rocks like chalk and limestone are dissolved in sea water and then carried in solution. The load is not visible.
• • Suspension - small particles such as silts and clays are suspended in the flow of the water.
• • Saltation – where small pieces of shingle or large sand grains are bounced along the sea bed.
• • Traction – where pebbles and larger material are rolled along the sea bed.
• Swash - Movement of water towards the beach
• Backwash - Movement of water away from the beach
• Longshore Drift: Sediment is carried by the waves along the coastline. The movement of the material is known as longshore drift. Waves approach the coast at an angle because of the direction of prevailing wind. The swash will carry the material towards the beach at an angle. The backwash then flows back to the sea, down the slope of the beach. The process repeats itself along the coast in the zigzag movement.

  
• Landscape

  An area whose character is the result of the action and interaction of natural and human factors
• Relief

  A term used to describe the height above sea level, shape of landscape features, and steepness of the slopes - the height and shape of the land. It's determined by geology.
• Hard, resistant rocks such as granite and slate form some of the Uk's most dramatic mountain ranges.
• Geology

  The study of rocks and their compositions
• Soft rocks such as clays and limestone often form low-lying plains and gently rolling landscapes.
• Scree

  Broken Rock