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Coasts (landforms) - Coggle Diagram

- - - - Cliff erosion
      - Offshore
      - Rivers
      - Humans can also add sediment to beaches through beach replenishment, this is not usally to create beaches those.
    - - Gentle gradient
      - Ridges and runnels form parrel to the sea.
      - Cusps are formed at both beaches and are small, semi-circular depressions that form temporally where both swash and backwash are the same.
    - - Steep gradient beaches
      - Storm ridges are created by storm waves hurling pebbles to the back of the beach.
        
        Berms are smaller ridges that form nearer the sea, these mark areas of high tide.
  - - - When longshore drift moves sediment in one direction this moves sediment along a beach and then into open water.
      - This then extends the beach along the stretch of coastline that the beach is on.
      - Storms add larger material to the spits, making them more permant.
      - The end of spits can become recoverd as waves refract on the end of the spit and deposit sediment at an angle to the orignal end.
      - When spits form along esturies they are limited in their expansion as the water flowing out of the estury will limit how far it can stretch.
  - - - Falling sea levels can lead to increased depsotion of heaveir material such as shingle.
      - If this material is deposited along a line connect an island to the mainland, when the sea levels drop further a shingle tombolo will have formed.
  - - - First the spit or bar forms.
      - Then as the area still has a reletivly high salinity it is colinised by salt-tolerant plants that help trap sediment.
      - This trapped sediment helps to raise the saltmarsh, this then reduces how long it is submerged for.
      - Less time submerged means that the water becomes less saline and it is colonised by more plants.
    - - Further inland the water becomes less saline and less turbid as well as the area spending less time submerged, this allows for greater biodivesity.
  - - - River entering the sea with a large sediment load.
      - A broad continetal shelf to provide an area for sediment.
      - Low energy enviroment.
      - Low tidal range.
    - - Upper delta
        
        Furthest inland.
        
        Out of reach from the tides.
        
        Only made up of fluvial deposits.
      - Lower delta
        
        Intertidal zone.
        
        Reguallary submerged.
        
        Made up of both river and coastal deposits.
      - Submerged delta
        
        Lies below mean water mark.
        
        Made up of mainly coastal sediment deposits.
        
        Represents the seward growth of the delta.
    - - Cuspate
        
        A pointed extension to the coastline that is shapped by regular, gentle currents.
        
        https://docs.google.com/drawings/d/1nnsEClrAWXBy9lWzNpz9-gxlXuPYqzdm3-1DF_1IKdE/edit
      - Arcuate
        
        Sediment enables the delta to extend seaward, but wave action is strong enough to smooth its edges.
        
        https://docs.google.com/drawings/d/1nQbq9OVa0lOgTZdT0kOzfiXGAfD7r8uKMtQHFtG26h8/edit
      - Bird foot
        
        Distributries branch out from the delta with sediment supply exceeding the rate of errosion.
        
        https://docs.google.com/drawings/d/1jgx_x8GQ5c_WmpbFv5l1TFRGBWsQbwwiA2lFfHl2i70/edit
- - - - Caves
        
        A point of weakness is eroded through wave action until it exapnds to create a cave.
      - Arches
        
        A cave is eroded further, this leads to the cave expanding backwards. On the other side of the headland another cave can form to speed up the process.
        
        Once the cave has broken through to the other side of the headland it has formed an arch.
      - Stacks
        
        Arches are erdoded durring storms and through sub-arial processes, this reduces the size of the bridge that conncects the two sides of the arch.
        
        As the arch expands and the bridge is eroded further the bridge will collapse, this then creates a standing section of the headland, this is called a stack.
      - Stumps
        
        The bottom of stacks are eroded until they can no longer hold themselves up, these stacks then collapse leaving a small lump of rock in the sea. This is called a stump.
  - - - These are narrow steep sided inlets.
      - Points of weakness are eroded by wave actions.
      - These can form tunnel like caves, which as they increase in size suffer from a roof collapse. This creates a geo.
    - - If part of a geo collapses along a master joint it may form a verticle shaft that reaches to the to of a cliff.
      - Durring storms water can force itself out of the top of a blowhole.
- - - - Human and naturally caused.
  - - - Deacrease in global temps increases the amount of preci[pitation falling as snow.
      - This snow turns into ice.
      - Ice is stored on land and not in the oceans.
      - This results in a reduction in the volume of water in the oceans and hence a drop in the sea levels.
      - Cooler tempretures also lead to an icrease in densitu of water molecules and therefore a reduced water volume.
    - - Increase in global temps leads to an increase in surface ice melting.
      - Melted ice water then runs off into the oceans.
      - Increased tempretures also leads to an expantion of water molecules and an increase in the volume of water.