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TOPIC 2B: Coasts - Coggle Diagram

- - - - For example...
        
        Managing NATURAL RESOURCES to ensure long-term productivity
        
        Managing FLOOD + EROSION RISK or relocating to safe areas
        
        Creating ALTERNATIVE LIVELIHOODS before existing ones are lost
        
        ADAPTING TO RISING SEA LEVELS by relocating, alternative building methods and water supplies
        
        EDUCATING COMMUNITIES to understand why change is needed and how to adapt
        
        MONITORING coastal change and adapting to unexpected trends
  - - - GROYNES
        Vertical timber/stone fences built 90 degrees to the coast which prevent longshore drift and encourage deposition (increased erosion downdrift)
      - RIP-RAP (ROCK ARMOUR)
        Large boulders, often used at the base of sea walls, which break up and dissipate wave energy (sediment may be deposited between the rocks)
      - REVETMENTS
        Permeable stone/timber/concrete structures which absorb wave energy, reduce swash distance, encourage infiltration and reduce dune erosion
      - SEA WALL
        Concrete wall reinforced with steel to provide a barrier against erosion and floods (if reflective can reduce beach volume)
      - ROCK BREAKWATER
        Large boulders placed offshore, which force waves to break early to reduce their energy and erosive force (deposition encouraged between breakwater and the beach)
- - - - Coasts can be split into sections. These are called sediment cells. There are 11 sediment cells in England and Wales.
      - SOURCES = where sediment comes from (e.g. cliffs, offshore bars)
        THROUGH FLOWS = movement of sediment along the shore (longshore drift)
        SINKS = areas of deposition (e.g. spits, beaches)
  - - - IGNEOUS
        
        Very slow erosion rate
        
        Crystalline with few joints
        
        e.g. granite, basalt, dolerite
      - METAMORPHIC
        
        Slow erosion rate
        
        Crystalline, foliation (crystals orientated in one direction which produces weakness)
        
        Often folded and fractured
        
        e.g. slate, schist, marble
      - SEDIMENTARY
        
        Fast erosion rate
        
        Clastic
        
        Geologically young
        
        Many bedding plains and fractures
        
        e.g. sandstone, limestone, shale
  - - - STRATA = different rock layers
      - DEFORMATION = how much rocks are tilted/folded by tectonic activity
      - FAULTING = major fractures that have moved rocks from their original position