river 2 waterfall plungepools floodplain n levees

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Waterfalls Sudden, steep and vertical flow of fast-flowing water falling from great heights Formed by river erosion

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Page 1: River 2 waterfall plungepools floodplain n levees

Waterfalls

• Sudden, steep and vertical flow of fast-flowing water falling from great heights

• Formed by river erosion

Page 2: River 2 waterfall plungepools floodplain n levees

Niagara Falls on Niagara River, Canada and USA

• formed by erosion of rock of different resistance

Page 3: River 2 waterfall plungepools floodplain n levees

Formation of Waterfalls

Page 4: River 2 waterfall plungepools floodplain n levees

Formation of Waterfalls• River flows across rocks of different

resistance.

Page 5: River 2 waterfall plungepools floodplain n levees

Formation of Waterfalls•River erodes the less resistant rock more rapidly•This cause a change in the gradient of the river

course.

Page 6: River 2 waterfall plungepools floodplain n levees

Formation of waterfalls• Over time, river plunges from a great height to

hit the riverbed below, • This forms a waterfall.

Page 7: River 2 waterfall plungepools floodplain n levees

Formation of plunge pools

•Repeated pounding of the river bed leads to a depression at the base of a waterfall •A plunge pool is formed.

Page 8: River 2 waterfall plungepools floodplain n levees

Floodplain Areas of low-lying ground adjacent to a

river at the lower course

Page 9: River 2 waterfall plungepools floodplain n levees
Page 10: River 2 waterfall plungepools floodplain n levees

Formation of Floodplain and Levee

Page 11: River 2 waterfall plungepools floodplain n levees

Formation of Floodplain and Levee

Page 12: River 2 waterfall plungepools floodplain n levees

Floodplain and Levee• During a heavy rainfall, river water overflows its bank. River loses speed as it

encounters friction.

Page 13: River 2 waterfall plungepools floodplain n levees

Floodplain and Levee• Deposition occurs as river’s energy decreases. • Coarser and heavier sediments are deposited

nearer to the river bank. • Finer and lighter sediments are deposited

further away.

Page 14: River 2 waterfall plungepools floodplain n levees

Formation of Floodplain and Levee

Page 15: River 2 waterfall plungepools floodplain n levees

Floodplain and Levee

• Overtime, the accumulation of fine sediments results in the formation of flat plains

Page 16: River 2 waterfall plungepools floodplain n levees

• Coarser and heavier sediments are acculumated

• Results in the formation of raised banks • Known as levees.