Rivers

What is a drainage basin?
An area of land that is drained by a river and its tributaries.
1 of 41
What is the watershed?
An area of highland that separated one drainage basin to another.
2 of 41
What is a source?
Where a river starts.
3 of 41
What is a tributary?
A smaller river following into a larger river.
4 of 41
What is a confluence?
Where two rivers or tributaries meet.
5 of 41
What is the main channel?
The main area where water flows.
6 of 41
What is an estuary?
The wide, tidal part of the river before the river mouth.
7 of 41
Upper Course
Narrow channel, shallow water, high bed load, fast flowing water.
8 of 41
Middle Course
Wider channel, gentle gradient, deeper water, more suspended sediment, slower flowing water.
9 of 41
Lower Course
Very gentle sloping valley, wide and flat floodplain, wide channel, deep water, little sediment.
10 of 41
Erosion
The wearing away of land either by water or the material that it carries.
11 of 41
Transportation
The carrying of material that has been eroded or deposited from on place to another.
12 of 41
Deposition
The dropping or depositing of material that has been carried by the river.
13 of 41
Types of Erosion: Hydraulic Action
Water hits against the banks weakening it.
14 of 41
Types of Erosion: Abrasion
Bits of material rub away the bank like sandpaper.
15 of 41
Types of Erosion: Attrition
Rocks knock into each other and break down.
16 of 41
Types of Erosion: Solution
Chemicals in the water dissolve rock from the river cliff and banks.
17 of 41
Types of Transportation: Traction
Boulders and big rocks roll along the bed.
18 of 41
Types of Transportation: Saltation
Small rocks and pebbles bounce along the river bed.
19 of 41
Types of Transportation: Suspension
Sediment and small particles are carried by the river.
20 of 41
Types of Transportation: Solution
Material is dissolved into the water
21 of 41
Features of Deposition
Heaviest material is dropped first, the river needs to be flowing quickly to allow heavy material to move, smaller material is lighter and easier to move.
22 of 41
V-Shaped Valley (1)
The river erodes vertically by stones, boulders and rock scrape and erode along the river bed.
23 of 41
V-Shaped Valley (2)
As the river erodes, it ends up flowing along way from the top, resulting in cliffs. Weathering causes the cliffs to crack.
24 of 41
V-Shaped Valley (3)
The loosened material slowly moves down the slope due to gravity or rainwater. Material falls into the river and is carried away.
25 of 41
Waterfall (1)
Soft rock is eroded underneath hard rock. Falling water and rock cause a plunge pool at the bottom where rocks have fallen. Hydraulic action and abrasion can occur.
26 of 41
Waterfall (2)
The hard rock above is undercut as erosion of the soft rock continues.
27 of 41
Waterfall (3)
An overhang forms which then collapses into the plunge pool to be broken up and washed away. The waterfall will then retreat upstream to form a gorge.
28 of 41
Ox Bow Lake (1)
Water flows faster on the outside of a bend, causing it to be eroded away. Material is deposited on the inside of the meander. The bend becomes a meander.
29 of 41
Ox Bow Lake (2)
The meander bends more and more until it is a tight loop. When the water level is high, the river has enough energy to go across the loop, rather than around it. This is called a meander cut-off.
30 of 41
Ox Bow Lake (3)
The river keeps to its new channel, so the loop is left as an ox bow lake which, over time, silts up and dries out.
31 of 41
Slip Off Slopes - inside bend
On the indide of the bend, the current is very slow with lacking energy. This causes lots of deposition, forming a slip off slope.
32 of 41
Slip Off Slopes - outside bend
On the outside of the bend, the current is fastest, causing lots of erosion to form a river cliff.
33 of 41
Floodplain (1)
Floodplains form due to erosion and deposition. Erosion widens the valley, taking away the interlocking spurs present near the source, and creating a wide, flat area.
34 of 41
Floodplain (2)
Lateral erosion, linked to meander migration, along with hydraulic action and abrasion cause this. Deposition is also partly responsible as, when it overflows, material is dropped. This sediment forms layers, building up the floodplain.
35 of 41
Levees (1)
During a flood, the floodplain is inundated. Larger sediment is deposited close to the channel as the river starts to lose energy. Smaller sediment is carried further away before it is deposited.
36 of 41
Levees (2)
This creates levees or large natural embankments close to the channel. Layers of sediment cover the floodplain.
37 of 41
RIVER SEVERN (1)
220 miles long,It starts in the Plynlimon Hills 740m above sea level, it flows through Shrewsbury, Bewdley and Gloucester.
38 of 41
RIVER SEVERN (2)
It has hydrology stations where the water is forced through gates to create energy from the water flow. It starts as peat bogs, but transforms into rapids with waterfalls and meanders.
39 of 41
Factors increasing the chance of flooding
Slow infiltration, fast through flow, hard soil, saturated soil, building on a floodplain, deforestation and a small drainage basin.
40 of 41
Factors decreasing the chance of flooding
Fast infiltration, slow through flow, decreased surface run off, soft soil, no building on a floodplain, forest, large drainage basin.
41 of 41

Other cards in this set

Card 2

Front

What is the watershed?

Back

An area of highland that separated one drainage basin to another.

Card 3

Front

What is a source?

Back

Preview of the front of card 3

Card 4

Front

What is a tributary?

Back

Preview of the front of card 4

Card 5

Front

What is a confluence?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Rivers resources »