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(iv) Ox-bow Lake : An ox-bow lake is an U shaped water body. It is formed when a wide

meander is cut-off from the main stream of a river to create a cut-off lake. This land
form is called an ox-bow lake for the distinctive curved shape that results from this
process.

Meanders Waterfall Flood Plain Ox-bow Lake

• Angel Fall (Highest) is located in Venezuela, South America.
• Jog waterfall is situated in India, in Asia.
• Victoria waterfall lies on the border of Zambia and Zimbabwe in Africa.

(v) Levees : The raised banks are called levees. These are formed due to the deposition of
sediments during flood period where the water over tops the river banks. The average
height of natural levees is about 10 metres.

(vi) River Valleys : These are the most significant erosional land forms carved out by the
rivers. These are formed in the mountainous regions. They are the result of vertical
erosion by rivers. These valleys have steep slopes.
(vii) Delta : As the river approaches the sea, its speed slows down and the river divides into
a number of streams called distributaries. Slowly it begins to deposit its suspended

material brought along with it. Thus each distributary forms its own mouth. The
collection of sediments from all the mouths forms a triangular structure called delta.

Levees V Shaped Valley Delta

Work of WavEs

The erosion and deposition of the sea waves creates several coastal land forms. The features
made by sea waves are :

(i) Sea Caves : These are formed due to the gradual erosion of weak and strongly jointed
rocks by sea waves. These joints are widened into large hollows that are called the

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