Geography p2

• Abrasion

  A form of erosion where loose material and sediment 'sandpapers' the walls and floors of the river, cliff or glacier
• Attrition


  Rocks bang against each other chipping away to make smaller, smoother rocks
• Backshore


  The upper beach closest to the land, including any cliffs or sand dunes
• Beach Nourishment


  The addition of sand and sediment to an eroding beach by humans. The new material will be eroded by the sea which saves the cliffs or sand dunes from erosion and recession
• Biological Weathering


  Rocks are broken apart by vegetation and roots, or chemical reactions from animal faeces erodes the rock face
• Concordant Coast


  A coastline where bands of alternate geology run parallel to the coast
• Corrasion


  A form of mechanical erosion where material and sediment in the sea is flung at the cliff-face as waves break against it, this breaks up the rocks making up the cliff
• Chemical Weathering


  The weak acid in rainwater will dissolve chemical compounds in the rock
• Discordant Coast


  A coastline where bands of alternate geology run perpendicular to the shore
• Drainage Basin


  The area of land drained by a river and its tributaries
• Dredging


  Rubbish and sediment are dug up from the bottom of the river
• Embankments


  The banks of the river are built up in brick and concrete, to increase the channel capacity
• Estuary


  The point at where the river meets an ocean, often muddy or silty. Sometimes estuaries become exposed at low tide or hazardous to traverse in a boat due to sandbanks
• Fetch


  The length of water over which the wind has travelled
• Floodplain


  The low lying and wide floor of a river valley. Floodplains are found in the lower course and tend to act as overspill for the river when its channel is full
• Floodplain Zoning


  Controlling where houses and buildings are built relative to the river to reduce their risk of flooding
• Freeze Thaw


  A form of physical sub-aerial weathering where water freezes in the cracks of a rock, expands and enlarges the crack. This weakens the rock overtime leaving it more open to erosion
• Geology


  The physical structure and arrangement of a rock
• Groyne


  A form of hard-engineering. Low-lying concrete or wooden walls, constructed perpendicular to the seafront and run out to sea. They encourage the trapping of sediment to reduce erosion caused by longshore drift or by winds
• Hard Management


  The use of concrete structures to reduce or halt the recession of a coastline. Includes: Groynes, Sea Walls, Rock Armour
• Highlands


  An area of land that is at a high elevation and tends to have a larger relief
• Hydraulic Action


  The pressure of compressed air forced into cracks in a rock face will cause the rock to weaken and break apart
• Igneous Rock


  Rock that has formed from volcanic activity, often cooled magma on the Earth's surface
• Impermeable


  A rock that does not allow water to pass through it
• Levee


  The banks of the river
• Longshore Drift


  The transportation of sediment along a beach. Longshore Drift is determined by the direction of the prevailing wind
• Lowlands


  An area of land that has a small relief, so tends to be flat and at a low elevation
• Mass Movement


  Where there is a large downhill movement of material usually from a cliff-face. Here, the rock is often weak due to erosion and the movement is caused by gravity
• Mechanical Weathering


  Sometimes called physical weathering, this is the breakdown of rocks due to forces, not chemical reactions
• Metamorphic Rock


  Rock formed under intense pressure and heat, often close to tectonic plate boundaries
• Permeable


  A rock that allows water to pass through it
• Relief


  The difference in the height of land for a particular region. A large relief means a region has a large difference between the lowest and highest points
• Rock Armour


  Large rocks or concrete blocks, used as barricades to reduce marine erosion at the base of cliffs
• Saltation


  A form of transportation where smaller sediment bounces along the sea bed pushed by currents. This sediment is too heavy to be picked up by the flow of the water
• Salt Marsh


  In sheltered bays or behind spits, salt and minerals will build up. Vegetation may establish, further stabilising the marsh
• Sand Dune


  A depositional landform, where sand and sediment build up around driftwood and accumulate over time
• Sea Wall


  A hard-management coastal defense, where a concrete wall is built parallel to the seafront, to redirect the energy of waves away from sensitive cliffs or the edge of a coastal town
• Sedimentary Rock


  Rock formed under intense pressure and heat, often close to tectonic plate boundaries
• Soft Management


  The use of natural materials and environmentally sustainable approaches to reduce coastal recession. Includes: Beach Nourishment, Managed Retreat, Sand Dune Encouragement
• Solution


  Acidic water dissolves chemicals from a rock face into the water. These chemicals can then be transported as chemical compounds in the water