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Rivers - Coggle Diagram

- - - - The river erodes downwards by hydraulic action. The valley is deepened by vertical erosion
      - As the river cuts down, the steep sides are attacked by weathering. This breaks up and loosens the soil and rock
      - The loosened material slowly creeps down the slope because of gravity or it is washed into the river by rainwater. The river carries it away
      - The end result is a steep-sided valley that has the shape of the letter ''V''
  - - - The river flows over an area where hard rock lies on top of an area of soft rock
      - The river erodes the soft rock faster. This develops a vertical drop where the hard rock and the soft rock meet.
      - At the base, a plunge pool develops due to the force of water falling along with its load swirling around at the base which wears away the case by abrasion
- - - - Small river, flows down steep slopes, erodes river bed vertically
      - Features
        
        V-shaped valley
        
        Interlocking spurs
        
        ridges of land that project from the sides of a river valley, alternating from each side like the teeth of a zipper
        
        Waterfalls
    - - Large river, flows quickly down gentle slopes, erodes river banks laterally
      - Features
        
        Meanders
        
        a bend or loop in a river, formed by the processes of erosion and deposition in flat terrain
        
        Wide valleys
    - - Very large river, flows on flat slopes, deposits lots of material carried from upstream
      - Features
        
        Ox-bow lakes
        
        a curved lake formed from a horseshoe bend in a river where the main stream has cut across the narrow end and no longer flows around the loop of the bend.
        
        Flood plains
        
        Deltas
        
        Levees
        
        a natural or artificial embankment, often made of earth, built alongside a river to prevent flooding by containing the water
- - - - Definition: The river wears away the landscape
      - Also known as fluvial erosion
      - River erosion works in 4 processes
        
        The fast-moving water breaks and wears away material from the bed and banks of the river. This processes is known as hydraulic action
        
        The broken material that is now carried along by the river is called the load. The load is thrown against the bed and banks of the river and wears them down. This process is known as abrasion
        
        The load itself is broken down further as particles bounce off one another and become smooth and rounded. This process is known as attrition
        
        The water can dissolve some of the minerals, eg limestone, on the river bed and banks. This process is known as solution