River Processes

River Processes

1. Weathering

   • Mechanical
     • Freeze-thaw
     • Erosion
   • Chemical
     • Carbonation
     • Acid rain
   • Biological
     • Plant roots
     • Burrowing animals

2. Erosion

   • Hydraulic action
     • Force of water breaks rock away from channel
   • Corrasion
     • Rocks scrape and rub against channel
   • Attrition
     • Rocks smash into each other, break into smaller bits..edges rub and rounded
   • Corrosion
     • Rocks dissolved by river

3. Transportation

   • Traction
     • Large bits pushed along river bed by force of water
   • Saltation
     • Pebbles bounced along river bed by force of water
   • Suspension
     • Small bits carried along by water
   • Solution
     • Soluble bits dissolve and carried along

4. Deposition

   • When river drops eroded material
   • When river slows down
   • Reasons why
     • Water volume falls
     • Increase in amount of material
     • River is shallower
     • River reaches it's mouth