DiSCoVeRInG rOCKS anD LanDFOrMS

Do you like hiking? I go hiking to many places: places with cliffs, beaches, caves, mountains, etc. Why does the landform change?

WHAT DO YOU THINK?

Are there rocks in this landscape? They are not living things. Should we

WHAT IS GOING ON AROUND YOU?

Rocks in landscapes are always changing. Sometimes, these changes are really slow. Can you see any of these changes around you?

WHAT CAN YOU DO TO HELP?

Gather your holiday photos and make an album with fun facts about landscapes. TAKE ACTION wHAT DO YOU NEED TO KNOW TO TAKE ACTION?

WHAT TYPES OF ROCKS CAN YOU IDENTIFY?

DO ROCKS FORM ALL LANDSCAPES?

HOW DO ROCKS ERODE?

WHAT IS THE EARTH’S STRUCTURE AND COMPOSITION? Layers of the Earth

1

2 Rocks

3 Rocks and uses

4 Looking for rocks in the landscape

5 Landforms and landscapes change

6 Erosion of rocks

WHAT DO WE USE ROCKS FOR?

DOES THE EARTH’S SURFACE CHANGE?

Is the Earth the same on the inside and on the outside? THINK

1

Look, listen and read.

The Earth is our planet. It looks like a gigantic, almost spherical ball. The land is made up of rocks, and most of the Earth is covered in water likes seas and rivers.

Earth’s layers

The biosphere

All the living beings that live on the Earth.

The atmosphere

The layer of air around the Earth. Air is a mixture of different gasses. We can’t see it, but we can feel il when it moves and the wind blows.

The hydrosphere

All the water on the Earth. It includes seas, rivers, groundwater, ice, snow and the water in the form of rain or clouds.

Atmosphere

Hydrosphere

The geosphere

The parts of the Earth underneath all the other layers. It has more layers inside it:

• The crust. The only part we can see directly: the part where we live. It is the top and the thinnest one. It is made up of solid rocks.

• The mantle. The layer below the crust. It is much thicker layer. The rocks are really hot.

• The core. It is the centre of the geosphere. It is made up of iron and other metals. This layers is even hotter than the mantle.

4 a) Hydrosphere 1) Rocks b) Geosphere 2) Living beings c) Biosphere 3) Air d) Atmosphere 4) Water

Match each layer to the correct component.

Order the layers of the geosphere from inner to outer part.

Crust Mantle Core

Choose one of the spheres of the Earth (biosphere, geosphere, atmosphere or hydrosphere) and define it to a classmate using keywords.

Rocks, minerals, three layers…

It is the geosphere!

1 Let’s study the geosphere with this experiment!

Step 1: Ask and adult for help if necessary. Take a pot with water and boil an egg.

Step 2: Peel part of the shell.

Step 3: Using a knife, cut it in half.

Hard-boiled egg Geosphere

2 In pairs, compare the result. Is it similar or not to the Earth’s layers?

NOW I KNOW…

Humans can’t travel deep inside the Earth. But thanks to geology, we know the three different layers of the geosphere.

Materials Egg Water Pot Knife

THINK

Why are rocks so diverse?

1 Look, listen and read. Rocks are everywhere around us. The geosphere is made up of rocks. They are really diverse, but all rocks have some common features.

Rock features

They are natural.

They are solid, but they can melt if they get hot.

They are made up of one or more components called minerals.

Rock classification

Components. Each rock has a characteristic combination of minerals.

Size of components. We can see some of the components clearly, but there are others we can’s see.

Appearance in nature. It depends on how the rocks were formed.

Rock sample

Minerals

3 a) Rocks are only be found in the hydrosphere. b) Some rocks are always liquid. c) Rocks are made up of only two minerals. d) We can use the microscope to see some of the rocks’ components. a) They melt. b) They evaporate. c) They burn. d) They disappear.

Read and decide if the following sentences are true or false. Correct the false ones.

What happens to rocks when they get really hot? Choose the correct option.

Do you want to know where to find rocks around you? See ‘Let me tell you’ at anayaeducacion.es a) Draw it in your notebook, including the components you can see. b) Write where you found it and what it looked like in the environment.

1 Look at the pictures. Can you see any rocks? Why?

2 In pairs, find a piece of rock. Study it under a magnifying glass.

3 Rocks are solid. It is true on the Earth’s surface, but there are some exceptions. Find out if liquid rocks exist and explain where we can find them.

NOW I KNOW…

Rocks are groups of minerals. We can classify them into three groups, depending on their original formation.

Your turn! CHECK

I think that liquid rocks exist in…

Have you got any rocks at home? Are they useful?

Granite. A rock in blocks

Features:

It is light grey and pink. Granite appears in enormous blocks. They are formed from molten rock that cooled and solidified underground.

Uses:

It is used in construction, to pave streets or the floors in houses, to make street furniture, in sculpture and more.

Layered rocks. Limestone, sandstone and clay

Limestone

Features:

It is solid and uniform. It can be whitish, cream, reddish or blue-grey.

Uses:

We use limestone blocks in construction and sculpture. We use ground limestone to make cement.

Features:

Sandstone Clay

Features:

It is yellowish, reddish or brown made up of grains of sand. We can see the grains with the naked eye.

Uses:

We can also melt sandstone to make glass.

It can be white, brown, reddish, grey or other colours. It is soft and impermeable. If we mix it with water, we get a paste to mould. If we heat it, it becomes really hard.

Uses:

Good to make containers, bricks, floor or wall tiles.

Features:

Slate. A squashed rock

It can be black or shades of reddish grey. It is made up of several sheets. They have a very smooth surface and they can break easily. It sometimes contains fossils.

Uses:

We use slate sheets for covering roofs. School pupils wrote on slate with chalk long time ago.

Find the odd one out.

Basalt Volcanoes

Thin layers Black

Match the rocks to their correct uses.

Soft Granite

Three components

Construction

Sandstone Clay Limestone

In pairs, think about a rock and its uses. Explain why you like or don’t like it.

I like slate because it was useful in the school.

1 Your sister played with your rock’s collection and now the rocks are mixed up. There are four different types of rocks.

a) Use the key to help you organise your rocks. Make your own key to identify them.

b) Do you use any technique to organise your ideas when you are learning something new? Explain it to your classmates.

I don’t like sandstone because it can break easily.

It has layers that break easily.

Light-coloured rock with three components we can see with the naked eye.

Slate

It doesn’t have layers that break easily.

Dark rock, can’t see the different components.

Cream-coloured rock, can’t see the different components.

We use rocks to make objects. The different characteristics of rocks are useful.

Basalt Limestone

CHECK WHAT YOU LEARNED

How do rocks affect landscapes? THINK

1 Look, listen and read.

The natural landscape in a specific place depends on the types of rocks it contains.

This dark-coloured arch is a basalt mass formed during an eruption long ago. It was eroded by the sea.

The badlands landscape on the Canary Islands is covered in rock fragments from inside volcanoes.

Granite forms huge masses. Over time, they emerge above ground.

Layered rocks are made up of materials. These materials gradually settled on the bottom of lakes or seas and, over time, transformed into layers of rock.

Granite masses break into rounded blocks over millions of years because of temperatures and humidity.

In some slate landscapes we can see the different layers squashed under a massive force.

Match the labels to the correct picture.

Erosion by the sea Volcano fragments

Emergence above ground a) Limestone. b) Clay. c) Granite. d) Sandstone.

Which rock does NOT belong in a landscape with rock layers?

Your turn!

1 Humans extract rocks from the quarries. This activity damages the natural environment.

a) Investigate a famous quarry in your province and look for information about what rocks or minerals are extracted.

b) Look at the pictures and say two advantages and two disadvantages. Follow the diagram:

In my opinion, a quarry is good because…

There are many types of rocks in nature. That’s why rocky landscapes are so diverse!

CHECK WHAT YOU LEARNED

Are the rocks on Earth’s surface indestructible or do they change?

1 Look, listen and read.

The Earth’s relief changes over time. It is still changing today. Some changes are very quick, like volcanic changes. Others are so slow that we don’t notice them (mountain formation or erosion of rocks).

How do volcanoes form?

There are hot rocks inside the Earth. Sometimes they melt and become a burning liquid.

When molten rock comes out of a volcano, it is called lava. A volcanic eruption is when lava breaks through the Earth’s surface.

How do mountains form?

When the lava cools, it forms rocks. They accumulate over time to create new landforms. Eruptions from underwater volcanoes can create new islands.

Mountains started as the seabed. They rose up slowly and grew to high altitudes.

When the hot, molten rocks inside the Earth move, they produce forces that push against the Earth’s crust.

The rocks in the crust fold, break and rise. It is when earthquakes happen and mountains are formed. This is a really slow process.

Read and decide if the following sentences are true or false. Correct the false ones.

a) The Earth’s relief does not change over time.

b) A volcano is a crack in the Earth’s crust.

c) The forces inside the planet cause cracks in the Earth’s crust and form rivers and oceans.

Read the labels and order the formation of a volcano.

Lava cools and it creates new landforms.

Rocks inside the Earth melt.

Molten rock and gases escape through cracks.

Lava emerges to the Earth’s surface.

Your turn!

See ‘Eruption on La Palma’ at anayaeducacion.es and answer these questions.

a. How long did the eruption last?

b. How did the island’s relief change?

1 Let’s do an experiment to understand how forces can deform rocks.

Step 1: Prepare several layers of different coloured modelling clay.

Step 2: Put them on top of one another and let them dry a little. They represent the rock layers in the Earth’s crust.

Step 3: Slowly apply force to both ends of the modelling clay. This simulates the forces inside the Earth.

2 What does it happen? Compare the results with your classmate.

Landscapes change very slowly. That’s why they always look the same.

How do air and water affect rocks?

1 Look, listen and read.

The cold makes water freeze. It breaks the rocks into pieces. They fall down the hillside.

The substances in rainwater can slowly dissolve and erode rocks.

The action of the cold and rain

The action of rivers

Eroded rocks

In a desert, wind erodes rocks. It transports and deposits the dust and grains of sand, forming dunes.

The action of the wind

The action of the sea

Rivers carve out valleys in the upper course. They break off pieces of rock, drag them downriver and make them rounded.

Rivers deposit sand and silt at their mouth, near the coast.

The sea breaks and erodes coastal rocks to create cliffs and beaches.

Look at the pictures and choose the correct erosion factor.

Look for pictures of erosion examples on the Internet. Can your classmate describe what factor affects the landscape in each of them? Then, duplicate your pictures and create a memory game.

What does this picture show?

Your turn!

It is a dune. The wind transports particles of sand and creates dunes.

See ‘Let me tell you’ at anayaeducacion.es to find out how the rocks on the Earth change.

1 In pairs, prepare two identical boxes. Each box has a miniature sloped terrain made of sand and stones.

Step 1: Pour water onto the high part of box A to simulate rain.

Step 2: Use a hairdryer on the high part of the box B to simulate wind.

2 Describe the different results in each case.

Water and air act on the rocks very slowly: they erode them and deposit the pieces in lower areas.

CHECK WHAT YOU LEARNED

It has three layers.

The geosphere is made up of Natural origin

Solid

The atmosphere

Basalt. Hard rock and it appears in volcanic landscapes.

Made up of minerals

Granite. Three different components. It appears in enormous blocks.

Slate. Black. It is made up of several layers and has a very smooth surface.

Limestone, sandstone and clay. They exist in thick layers. Layers can be horizontal, slanted or folded.