River erosional landforms

 Topic 7: River erosional landforms

Formation of Ox bow lake

• Form at the lower course of the river where meander become wider.

• Erosion on outer/concave bank of meander,

• Deposition on the inner bank,

• Increase size of meander, narrow its neck,

• Eventually river breaks through,

• Creates a temporary island,

• Short cut through meander neck becomes main channel, end of former meander silt up.

Cut off/ ox- bow lake

Formation of a meander

• Meander is a bend in a river

• It’s a result of erosion and deposition

• Resistant rock layers cause the river to change its course

• Meander forms as moving water widens the valley

• Slower flowing water, on the inner banks, less energy and will deposit silt forming a slip off slope

• Faster flowing water, on the outside bank cause more erosion (e.g. hydraulic action, abrasion) forming a cliff

Cross section of the meander