Floodplain formation
The floodplain is an area of relatively _____ land on either side of the channel. It is formed by
downstream ________ migration of __________. This occurs because the point of maximum erosion is just
downstream of the centre of the meander bend. As well as meander deposits, the floodplain consists of
________ deposits from times of _______. As the river overflows its channel, there is a reduction in
__________ (due to the sudden increase in wetted perimeter and the hydraulic radius which in turn will produce
an increase in _______ and a corresponding decrease in velocity) and any coarse sediment will be quickly
_______.
overbank
flat
velocity
meanders
deposited
lateral
flood
friction
Levee formation
When a river _______ its banks the _________ produced by the flood plain cause material to be
________. The ______ material is dropped first to form a small, natural __________ alongside the channel.
These deposits form distinct ridges on the floodplain, called _________. The finer sediment load is slowly
deposited from the flood waters as they sit on the floodplain and forms a fertile deposit called ________. If,
later on, the river bed is raised by deposition of material, these embankments are sometimes _________
strengthened and heightened to try to contain the river. Some rivers flow above the level of their flood plains
which means that if the levees collapse there can be serious danger to life and property. Levees sometimes have
a ________ structure due to a series of flood events with the ________ material nearest the channel due to
sorting.
deposited
artificially
Overflows alluvium
largest
layered
embankment
friction
coarsest
levees
Floodplain formation
The floodplain is an area of relatively _____ land on either side of the channel. It is formed by
downstream ________ migration of __________. This occurs because the point of maximum erosion is just
downstream of the centre of the meander bend. As well as meander deposits, the floodplain consists of
________ deposits from times of _______. As the river overflows its channel, there is a reduction in
__________ (due to the sudden increase in wetted perimeter and the hydraulic radius which in turn will produce
an increase in _______ and a corresponding decrease in velocity) and any coarse sediment will be quickly
_______.
overbank
flat
velocity
meanders
deposited
lateral
flood
friction
Levee formation
When a river _______ its banks the _________ produced by the flood plain cause material to be
________. The ______ material is dropped first to form a small, natural __________ alongside the channel.
These deposits form distinct ridges on the floodplain, called _________. The finer sediment load is slowly
deposited from the flood waters as they sit on the floodplain and forms a fertile deposit called ________. If,
later on, the river bed is raised by deposition of material, these embankments are sometimes _________
strengthened and heightened to try to contain the river. Some rivers flow above the level of their flood plains
which means that if the levees collapse there can be serious danger to life and property. Levees sometimes have
a ________ structure due to a series of flood events with the ________ material nearest the channel due to
sorting.
deposited
artificially
Overflows alluvium
largest
layered
embankment
friction
coarsest
levees