Lesson 3 The Rhine

• Aardrijkskunde
• Middelbare school
• havo, vwo
• Leerjaar 2

Lesson 3

Erosion

At the end of the lesson you can ...

1. Explain what erosion is.
2. Explain the difference between a U valley and a V valley. 
3. Explain the three forces responsible for erosion. 
4. Name different characteristics of different mountain ranges. 

HW

What two types of weathering are there?

What three types of mechanical weathering are there.

Explain how chemical weathering takes place.

Rocks are being moved

• Weathered material is carried away by rivers, glaciers and by the wind.
• In this process, erosion occurs.

Erosion

• = the wearing away of rock under the influence of water, ice or by the action of wind, moving the rock. 
• The big difference between weathering and erosion is that erosion always involves a transport agent.

Erosion by rivers

• Weathered rock enters rivers. 
• Rocks collide and rub against each other. 
• Pieces break off. 
• Stones are rounded off. 

Erosion by ice

• Glacier: packs of ice sometimes hundreds of metres thick. 
• High in the mountains; precipitation falls as snow. 
• New snow compresses and
  becomes ice: firn.
• Carried material is sedimented
  --> terminal moraine. 

Valleys

• A river valley has a V-shape and a glacial valley has a U-shape.

?

?

Glacial valley

River valley

Worksheet valleys

• Make the worksheet about U- and V-valleys. 
• Talk softly with your neighbour buddy. 
• Raise your finger if you have a question.
• Finished? Read and markt the important parts of lesson 3.

Erosion by wind

• Wind lifts sand.
• Sand scours along e.g. rocks.

Landscape cycle

= the whole process of weathering, erosion and sedimentation. 

Relief

• Variations in height = relief
• Lowlands = 0-200 meter
  
• Hill country = 200-500 meter
  
• Low mountain range = 500-1500 meter
  
• High mountain range = 1500 meter and
  higher
  

What relief are these mountains?

Mountain ranges

• Mountains crumble and wear away through
  weathering and erosion.
• Mountains with a lot of relief and high, sharp peaks --> young mountain ranges
• Mountains with little relief and low, round tops --> old mountain ranges

Young or old mountain?

Young or old mountain?

Young or old mountain?

Young or old mountain?

Young or old mountain?

Get to work!

1. Read lesson 3 completely
2. Mark all the important sentences
   
3. AG: Make exercises 1, 2, 3, 4, 5 & 6
   H: Make exercises 1, 2a, 2b, 2c, 4, 5 & 6

At the end of the lesson you can ...

1. Explain what erosion is.
2. Explain the difference between a U valley and a V valley. 
3. Explain the three forces responsible for erosion. 
4. Name different characteristics of different mountain ranges. 

What is erosion?

What three transport agents cause erosion?

What is the difference between a U and V-valley?

What reliefs are there? Name + heights

What is the difference between an old and a young mountain range?