How do rivers create landforms?

Starter:

Name three river

processes that create

landforms(3)

Simple answer

1)Erosion (you could name an example, e.g. hydraulic action, abrasion, attrition, corrosion)

2)Transportation (e.g. saltation, solution, suspension)

3)Deposition

Rivers game

• Can you recognise the features of the river from yesterday?

• Noughts and crosses game

Stages of river• There are three stages to a river's life.• Stage 1, the Upper Course, is a youthful river. This when the

river is a narrower stream. It starts as a trickle then becomes fast flowing because it flows down through steep land. There are lots of stones and boulders for the water to flow over.

• Stage 2, the Middle Course, is the mature river. This is the river in its middle age where it is beginning to flow more slowly. Other rivers join as tributaries. The middle course is where the river starts to become wider and deeper. The land which the river flows over is becoming flatter. The river starts to meander or bend in the middle course.

• Stage 3, the Lower Course, is the river in old age. This is where it flows slowly towards its mouth at the sea. It is very wide and deep. The lower course is where the river becomes its widest and deepest. This course is found closest to the sea where the river has its mouth. The flat area of land by the river banks is known as a floodplain. Farmers grow crops here and it is vulnerable to floods.

The upper stage of a river

Write down any key words about the characteristics of the upper stage from this clip

Upper course video

Interlocking spurs

• Identify on an OS map• Draw a labelled sketch• Explain formation

Upper River FeaturesThese are mainly formed by EROSION.

On the map below label:1. Source2. Interlocking Spurs3.Waterfalls

Draw a labelled sketch

• Figure 1.17 page 11

Explain how V-shaped valleys form• Copy and complete:

– A river carries along its bed. The material cuts downwards (vertical ) relatively quickly, deepening the bed of the river. After periods of heavy rain, soil on the valley sides slowly moves downhill under . The valleys forms a V-shape as it is faster than it is .

Deepened Gravity ErosionMaterial Widened

Waterfalls

• Identify from an OS map• Draw a labelled sketch• Explain how waterfalls are formed

Draw a labelled sketch

Explain how waterfalls are formed• Copy and complete:

– The hard, surface rock is eroded more slowly and so is left unsupported as the underlying _____

rock is more quickly by the river. In time the resistant rock ledge will collapse due to

. This material will be swirled around by the river, widening and the plunge pool at the foot of the waterfall. Over a period of time, as more rock collapses, the will slowly retreat leaving a steep-sided gorge.

waterfall deepening gravityEroded resistant softer

Middle Course

The middle stage of the river: Meanders1. Identify some meanders from the OS map extract2. How does this area attract tourists? Use map evidence in your answer. (4)3. What efforts have been made to make this area sustainable. Use map

evidence in your answer (2)

Meander Video

Sketch a meander

• Page 12 Figure 1.22

Meanders Explanation

• Copy and complete:– When rivers flow over flatter land, they develop large

bends called . As a river goes around a most of the water is pushed towards

the outside causing increased . The river is now eroding into its banks rather than downwards into its bed, a process called

erosion. On the inside of a bend there is much less water. Therefore the river is shallow and slow-flowing. It cannot carry as much and so sand a shingle will be .

deposited meanders erosionbend sideways lateral material

Middle course - meanders

Lower Course

Middle + Lower course video

The lower course1. Identify: a) Floodplain, b) a meander2. What will happen to the large meander in the future? You may wish to draw a diagram to

support your answer (4)

Lower course

• The lower course is where the river slows down as it nears the sea

• Land is flat and little erosion happens• Lots of deposition occurs, particular at the

mouth• The floodplain is used by farmers as the soil is

rich, but it is at risk of flooding

Hydro song/poem

• Using the textbook and all the keywords, write a song or poem to describe the hydro cycle

• Use pages 66 and 67 to help with terms

Common exam Qs

• These Qs come up often in exams:

- Locate features on diagram of river- Explain the main ways rivers erode- Explain how rivers transport material- Describe and explain how landforms changed

along the course of a river

Stages of a River

Upper Stage Middle Stage Lower Stage

Erosion Active vertical mostly Active vertical and horizontal erosion

Some horizontal but not much erosion

Gradient Steep, steep valley sides Becoming flat Flat

Deposition Some boulders too heavy to be transported in small stream

Deposition inside meander bends

Lots of deposition especially near mouth where river slows

Depth Deep Deep in places Shallow (because of deposition)

Velocity Fast Medium Slow

Width Narrow Wide in parts Very wide

Volume Very low Medium Large

Landforms Waterfalls, V-shaped valley, gorges, interlocking spurs

Small meanders, oxbow lakes, small floodplains

Floodplains, mouth, delta, estuary, large meanders, oxbows