Meanders
Water flows fastest on the outer bend = channel is deeper+ less friction= water being flung - towards the outer bend as it flows around the meander= greater erosion = deepens the channel= reduction in friction = increase in energy= greater erosion.
This lateral erosion = undercutting of the river bank + formation of a steep sided river cliff.
Inner bend water is slow flowing= low energy zone= deposition = shallower channel= increased friction = reduces the velocity =reducing energy= further deposition= a small beach of material builds up on the inner bend= slip-off slope or point bar.
Helicoidal flow= water in a meander flows in a corkscrew like movement - moves from the inside of the bend towards the outside of the bend.
Meander = asymmetrical in cross-section = deeper on the outer bend - greater erosion+ shallower on the inside bend - an area of deposition.
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