§1.2 Rocks change

• Aardrijkskunde
• Middelbare school
• havo
• Leerjaar 2

Start-up exersice 

Write down two things you learned last lesson. Use your books to help you if needed

Language to use

What I remember mostly..

We discussed the difference between..

What interested me most was..

Write down two things you learned last lesson. Use your books to help you if needed

§1.2 Rocks change

Lesson targets

- You know the difference between mechanical and chemical weathering and how rock weathers

- You understand why the climate affects the nature and speed of weathering.

- Using a drawing you can explain how limestone caves are formed. 

Young mountain range

Old mountain range

Welk gesteente hoort bij welke omschrijving?

Rocktype that you can recognise by the spotted colours

Petrified remains of plants or animals found in rocks

This rock forms when molten rock hardens. This can be inside (magma) the earth or outside (lava) it.

Igneous rock

Granite

Fossils

Why is it impossible to find fossils in igenous rocks?

Weathering

How can you tell these rocks are weathered?

 What is weathering?

 rock crumbling under the influence of the weather and plant growth

Chemical weathering 

Mechanical weathering

Note!

Note!

Causes of mechanical weathering

1. frost: water freezes over during winter, cracks form

2. Big temperature differences in an area> desert

3. Biological weathering: plant roots push rock apart

1

1

2

3

3

Note!

Chemical weathering

• With chemical weathering the composition of the rock changes
• Due to a chemical process the rock disolves
• This can form caves

Note!

Limestone caves

Hoe ontstaan deze grotten (kalksteen)?

This is due to chemical weathering. Via cracks in the rock rainwater can seep through the limestone. The acidic water can desolve limstone causing caves. You often find stalactites and stalagmites in these caves. 

Mechenical weathering

chemical weathering

Cold climates

warm climates

Lots of precipitation needed

some precipitation is enough

Closer to the poles

closer to the equator

Huiswerk

Please write your homework down in your diaries. Check the homework on the whiteboard

Weathering still dificult?

start-up exercise

Discuss with your neighbour which kind of weathering you see in the pictures. Also explain why you think so.

Language to use

A could be a... where as b is possibly a...

On one hand it might be... on the other hand..

... could be a clue for it being a .. 

Find a photo online that shows a weathered landscape. Add which type of weathering this is.

Write down 2 things you learned last lesson

create.kahoot.it

Write down one thing you do not understand (yet) this lesson