Globe Academy Science Department Year 8 Rocks and Rock ... summ… · True False a The movement of pieces of rock is called weathering. ... texture The scientific word used to describe

Globe Academy Science Department Year 8 Rocks and Rock Cycle Homework Booklet Contents: Topic Date

Set Date Due

Feedback/ Marking

1 Homework 1: Weathering

2 Homework 2 Transportation of rocks

3 Homework 3Changing Rocks

4 Homework 4 Hot Rocks

5 The Rock Cycle

Homework 5

6 Homework 6 Revision and Self

Assessment

Look after this booklet. You will need to pay for a replacement. Name: ______________________________________

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A B

C D

biological weathering chemical weathering

freeze–thaw weathering onion-skin weathering

Answer these questions using the phrases in the box.

1 Label the four pictures.

2 Which type or types of weathering:

a are examples of physical weathering

b is caused by acidic rain

c need water to make them happen

d need temperature changes to make them happen

e happens to limestone faster than to other rocks

f are caused by expansion and contraction

g are not likely to happen in a desert?

3 Explain your answer to question 2 part g.

I CAN... • recall facts about different kinds of weathering • explain when certain types of weathering are likely to happen.

333 Exploring Science edition © Pearson Education Limited 2008

Home work 1 Weathering

7Hc(1) 7Hc(1)

Name 1 Are these statements true or false?

Class Date True

Name Class Date

False 1 Are these statements true or false?

a The movement of pieces of rock is called weathering.

b Bits of rock can be transported by rivers.

True False

a The movement of pieces of rock is called weathering.

b Bits of rock can be transported by rivers.

c Abrasion is when bits of rock knock into each other and wear away.

d The water in a stream is called sediment.

c Abrasion is when bits of rock knock into each other and wear away.

d The water in a stream is called sediment.

e The faster the water is moving, the smaller the pieces of rock it can carry.

f The wind can move big pieces of rock.

e The faster the water is moving, the smaller the pieces of rock it can carry.

f The wind can move big pieces of rock.

g Glaciers can move big pieces of rock. g Glaciers can move big pieces of rock.

h Rivers deposit sediments when they slow down. h Rivers deposit sediments when they slow down.

2 Write correct versions of the statements that were wrong. 2 Write correct versions of the statements that were wrong.

I CAN... Exploring Science

I CAN... Exploring Science

• recall how bits of rock are transported and deposited. • recall how bits of rock are transported and deposited.

edition © Pearson Education Limited 2008 edition © Pearson Education Limited 2008

7 H c

7Hc(5)

Homework 2 Moving on Home work 2 Moving on

Word Pronunciation Meaning crystals kris-tals Pieces of a mineral with sharp edges. geologist A scientist who studies rocks. grain Tiny piece of a rock or mineral. igneous rock ig-nee-us A rock formed from interlocking crystals. interlocking When crystals fit together with no gaps between them. metamorphic rock met-am-orf-ick A rock formed from interlocking crystals that are often

lined up in layers. minerals The chemicals that rocks are made from. mixture Two or more different kinds of materials that are not

chemically joined to each other. permeable per-mee-ab-ul Permeable rocks let water soak through them. porous poor-us Porous rocks have tiny holes in them. property A description of what a material is like and how it behaves. sedimentary rock sed-im-ent-tree A rock formed from grains stuck together. The grains are

often rounded. texture The scientific word used to describe the shapes and sizes

of the crystals or grains in a rock.

7H

7 H

Word Pronunciation Meaning biological weathering When rocks are worn away or broken up because of the

activities of living things. For example, growing plant roots can split rocks apart.

chemical weathering When rocks are broken up or worn away by chemical reactions, usually with rain water.

contract Get smaller. expand Get bigger. freeze–thaw action A type of physical weathering that happens when water

gets into a crack in a rock and freezes. The freezing water expands and makes the crack bigger.

onion-skin weathering A type of physical weathering which can be caused by repeated heating and cooling. Rock is peeled off in layers.

physical change fizz-ick-al A change that does not involve new chemicals. Melting and freezing are examples of physical changes.

physical weathering When rocks are worn away or broken up by physical processes such as changes in temperature.

Page 1 of 2

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Glossary of key words

Word Pronunciation Meaning calcium carbonate The chemical from which the shells of most sea creatures

are made. The main chemical in rocks such as limestone and chalk.

cementation sem-men-tay-shun A process in which water is squeezed out of the spaces between pieces of rock leaving behind mineral salts that stick (cement) the rock pieces together.

cemented sem-men-ted Something that has been stuck together. chalk Soft white or grey rock formed from the shells of small sea

animals. compaction com-pack-shun When layers of sediment or rock are squashed by the

weight of sediment above them. fossils The shapes of plants or animals preserved in rock. limestone A sedimentary rock made from the shells of dead sea

creatures consisting mainly of calcium carbonate. oolite oo-lite A type of limestone formed when water evaporates and

leaves calcium carbonate behind.

7H

Word Pronunciation Meaning abrasion ab-ray-shun When rock fragments bump into each other and wear away. deposits When moving water drops fragments or grains of rock. erosion eh-rO-shun The movement of loose and weathered rock. glacier gla-see-er Ice that fills a valley and moves slowly downhill. sediment Rock grains and fragments dropped on the bottom of a

river, lake or sea. transport The movement of rock grains and fragments by wind,

water or ice.

7 H

Word Pronunciation Meaning aggregate Sand, gravel and other stones used in building roads and

making concrete. coal A rock made from the remains of plants. Coal is a fossil fuel. fossil fuels Coal, oil and natural gas – all fuels that were formed from

the remains of dead plants or animals. natural gas Fossil fuel formed from the remains of dead plants and

animals that lived in the sea. oil Fossil fuel formed from the remains of dead plants and

animals that lived in the sea.

Exploring Science edition

© Pearson

Education Limited 2008

Glossary of key words

7H

Tick the boxes that apply. Or use traffic lights to show how confident you are (red = ‘I don’t know this’; orange = ‘I’m not very confident about this’; green = ‘I’m confident I know this’).

7 H


Level Ladder

Level At the end of the Unit: I can do this This needs more work

Working towards Level 4

Sort rocks into groups based on texture.

Describe rock textures. Level 4

Recognise that quarrying can affect the environment.

Carry out a fair investigation.

Recall that rocks are composed of grains of minerals.

Recall the ways in which rocks are weathered.

Identify whether rocks are permeable or impermeable.

Level 5

Recognise that people have not always explained features of landscapes in the way we do now.

Recognise that geologists from different countries collaborate and exchange ideas.

Recognise the sort of evidence that geologists look for in rocks to work out how they were formed.

Describe how rocks layers can be used to provide evidence for a sequence of events.

Recall that layers of deposited sediments turn into layers of sedimentary rocks.

Level 6

Discuss the advantages and disadvantages of quarrying for materials.

Use ideas about weathering, erosion, transport and deposition to explain the differences between different sedimentary rocks.

Recognise that geology relies heavily on observation rather than experiment, unlike many other areas of science.

Plan a safe and fair investigation to produce accurate measurements.

7H

Name Class Date

7 H


7H Level Ladder (continued)


Make simple statements about how sedimentary rocks were formed based on their texture.

Explain why sedimentary rocks are often permeable.

Explain how rocks are weathered by chemical and physical processes.

Describe the different ways in which grains can be transported.

Explain how sediments are turned into rock.

Level 7

Make more detailed statements about how sedimentary rocks were formed based on their texture and other features such as cross-bedding.

Make links between the weather in an area and the expected types of weathering.

Explain how fossils can be formed.

Explain how fossils can be used to date rocks.

Level 8 Describe how the features of limestone scenery were

formed (joints, sinkholes, dolines).

1 a This diagram shows one way in which metamorphic rocks can be formed.

Label the diagram using words from the box.

b What has made the metamorphic rock form in the diagram? Tick one box.

heat and pressure heat only pressure only

2 Quarzite is a metamorphic rock made when sandstone is heated and compressed. The drawings show the textures (the way the grains are arranged) in sandstone and quartzite.

a Write the correct names under the drawings.

________________________ ________________________ b Explain how you worked out your answer.

_______________________________________________________________________________________

_______________________________________________________________________________________

Home work 3 Changing rocks

metamorphic rock magma sedimentary rock

3 When rocks are heated or compressed, the kind of metamorphic rock formed depends on how high the temperature and pressure is. Slate, schist and gneiss are all metamorphic rocks that can be made from mudstone.

Match up the descriptions of the rocks with the drawings showing their textures.

8Hc(5) Changing rocks (continued)

I CAN... • recall the processes that can form metamorphic rocks • identify the textures of different metamorphic rocks from

their descriptions.

Slate is made from mudstone. The crystals are very small and in layers.

Gneiss is formed at the highest temperature and pressure. Some of the minerals form thick coloured bands.

Schist is made when slate is heated and compressed. The crystals are bigger than the crystals in slate, and are usually lined up in wavy lines.

365

The mantle can melt in places, forming…

crust inner core mantle outer core

When magma cools down, it forms rocks called…

If magma cools down quickly, it forms…

If magma cools down slowly, it forms…

When magma reaches the Earth’s surface, we call it…

igneous rocks with small crystals, e.g. basalt.

igneous rocks with large crystals, e.g. granite.

magma.

lava.

igneous rocks.

the speed of cooling affects the sizes of crystals.

1 Inside the Earth.

Label the parts using the words in the box.

2 Draw lines to match up these sentence halves.

Home work 4 Hot rocks

also happen if water gets into a crack in the rock nto ice, and makes the crack wider. This kind of p on.

7H

Rock textures Rocks are made of grains. Each grain is made of a chemical called a mineral. The texture of a rock is a description of the size and shape of the grains.

Sandstone has rounded grains. It is permeable, because water can get into gaps between the grains.

Granite has interlocking grains. The interlocking grains are sometimes called crystals. Rocks with interlocking grains are not porous.

7 H Weathering

Rocks can be worn away. This is called weathering.

Chemical weathering happens when rain water reacts with minerals in the rock. Rain water is slightly acidic, because it contains dissolved gases.

Physical weathering can happen in different ways. The minerals in a rock expand if the rock gets hot, and contract if it cools. These changes in size can produce strong forces. If the rock is heated and cooled over and over again, the forces can make cracks in the rock. This is called onion-skin weathering.

Physical weathering can expands when it turns i called freeze–thaw acti

and freezes. Water hysical weathering is

Biological weathering is when rocks are broken up or worn away by plants and animals. For example, plant roots can grow into cracks in rocks and make the cracks bigger.

Page 1 of 2

208 Exploring Science edition © Pearson Education Limited 2008

Summary Sheets

d .

),

e

7H

Forming sedimentary rocks Fast-moving water can move larger pieces of rock than slow-moving water. Rivers slow down when they flow into a lake or the sea. The slow-moving water cannot carry all of the sediment, so some of it is deposited on the bottom. Sediments often form layers. Layers of sediment can also form when sea water evaporates and leaves salts behind.

Sometimes dead plants or animals fall to the bottom of the sea. If their remains get covered by other sediments they may form fossils. When a dead organism forms a fossil, its form can still be seen because its hard parts have been turned into stone. Fossils can help geologists find out how rocks were formed.

If a lot of plant material is buried at once, it may turn into coal. When tiny sea plants and animals get buried they sometimes turn into oil or natural gas. These are all fossil fuels.

The higher layers squash the lower layers, squeezing out the water from the gaps between the grains of sediment (compaction). Dissolved minerals in the water can crystallise in the gaps as a ‘glue’ that sticks the grains together (cementation).

Evidence in the rocks Geologists can explain how sedimentary rocks formed using evidence in the rocks.

Rounded grains in the rock show that the sediments must have been transported for a long time, because abrasion has smoothed them. Sharp-edged grains show that the grains were probably not transported for very long.

Small grains show that the grains were deposited by wind (which can only move very small particles or by slow-moving water. Rocks with large grains, or with a mixtur of grain sizes (such as conglomerate) must have been deposited by fast-moving water.

Layers in the rock show that the river that deposited them changed speed from time to time.

layers of sedimentary rock

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Erosion and transport Weathered pieces of rock fall to the bottom of cliffs. This movement of bits of rock is called erosion. The bits of rock can be transported away by flowing water, wind and ice (glaciers). Pieces of rock bump into each other while they are being transported, and bits get knocked off them. This is calle abrasion. The bits of rock carried by a river are called sediment

Summary Sheets (continued)

Level I have… Yes Working towards level 4

stated that rocks can be put into three different groups. explained that sedimentary rocks are formed from bits of rock stuck together.

given some examples of rocks I see around me and described how they look different.

explained that different rocks have different properties (for example that some rocks are harder than others).

Level 4 described the different properties of sedimentary, igneous and metamorphic rocks.

Stated that the Earth is constantly changing. described some examples of places where we can see that rocks have changed (for example when statues become worn).

explained that sedimentary rocks are often porous and easily weathered. given some examples of places that we use rocks (for example for building) and linked the properties of the rocks to the things they are used for.

Level 5 described the different weathering processes. described how rock fragments are transported and abraded. explained why sediments are deposited, and how sedimentary rocks are formed.

linked the way that sedimentary rocks are formed to the fact that some sedimentary rocks are older than others.

used the texture of sedimentary rocks as evidence to explain how they were formed.

explained that igneous rocks are more resistant to weathering than sedimentary rocks, and how this may affect the landscape.

Level 6 described how the crystal size in igneous rocks depends on the rate of cooling.

explained how the size of crystals in igneous rocks depends on how fast the magma or lava cooled, using ideas about particles.

described the circumstances in which igneous rocks with different crystal sizes form, using ideas about heat transfer and cooling rates.

Your task is to write the life story of a boulder called Rocky. The story should be presented as a storyboard for a cartoon to explain the rock cycle to younger children. You

should also:

• suggest what ‘Rocky’ should be saying in each picture

• add notes on how each should be animated

• produce a set of teacher’s notes

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Limited 2008

Assess yourself!

Level I have… Yes Level 7 explained that the size of the crystals in an igneous rock is evidence for the cooling condition

under which it formed.

described how metamorphic rocks are formed. stated that all rocks are connected by the rock cycle. explained why metamorphic rocks are often layered or show alignment of crystals. explained how rocks are changed and formed during the rock cycle. explained the layers in a metamorphic rock, can indicate the heat/pressure it has been subjected to.

used my knowledge of the rock cycle to explain that some processes in the cycle are very fast and some are very slow.

explained that the existence of metamorphic rocks around an intrusion of igneous rock is evidence that the metamorphic rocks were formed by heating the existing rock.

linked the existence of metamorphic rocks to the fact that the rocks have been in contact with hot magma or have been buried within the Earth.

Level 8 described how and why the minerals in a sedimentary rock may be different from the original rock from which the sediments came.

explained how rocks can be buried using ideas about plate tectonics. explained why volcanoes and/or earth movements occur in particular places, using ideas about plate tectonics.

applied my knowledge of plate tectonics to explain that some areas of the world may be at greater risk of earthquakes than others and described how this will affect the ways that people build.

EP given an idea of the timescales involved in the different parts of the rock cycle

Exploring Science edition © Pearson Education Limited 2008

8H Assess yourself! (continued)

Word Pronunciation Meaning basalt ba-salt An igneous rock with very tiny crystals. biological weathering When rocks are broken down due to the activities of living

things. For example, growing plant roots can split rocks apart.

cementation sem-men-tay-shun A process in which water flows through the spaces between pieces of rock leaving mineral salts behind which stick (cement) the rock pieces together.

cements sem-men-ts sticks chalk A soft white or grey sedimentary rock formed from the

remains of microscopic organisms, and so mainly made out of calcium carbonate.

chemical weathering When rocks are broken up or dissolved by chemical reactions, usually with rainwater.

classify To sort things into groups. climate The average weather conditions in an area, or for the whole

Earth. compaction com-pack-shun When layers of sediment or rock are squashed by the weight

of sediment above them. crystal Kris-tal Piece of mineral with sharp edges. deposit When moving air, water or ice drops rock fragments or grains

it has been carrying. earthquake When the earth shakes. erosion er-O-shun The movement of loose and weathered rock. fossil Any signs of past life, such as the remains of a dead animal or

plant, preserved in rock. geologist A scientist who studies rocks and the Earth. gneiss wice A metamorphic rock formed when schist is heated and squashed

more. It usually has bands of different coloured minerals.

grain Tiny piece of rock, usually made of one mineral. igneous rock igg-nee-us Rock made from interlocking crystals that are not in layers. limestone A sedimentary rock made from the remains of dead sea

creatures. metamorphic rock met-a-mor-fik Rock made from interlocking crystals that are usually lined up or

in layers. minerals The chemical compounds found in rocks. physical weathering When rocks are broken up by physical processes such as changes

in temperature. sediment Rock grains and fragments dropped on the bottom of a river,

lake or sea. sedimentary rock Rock formed from layers of sediment. It is often porous and

made of rounded grains. texture The scientific word used to describe the shapes and sizes of the

crystals or grains in a rock.

Page 1 of 3


Glossary of Key Words

Word Pronunciation Meaning basalt ba-salt An igneous rock with tiny crystals. bonds Forces holding particles in a solid together. crust The solid rocks at the surface of the Earth. crystal kris-tal A mineral with sharp edges. granite gran-it An igneous rock with large crystals. igneous rock igg-nee-us A rock formed when magma or lava cooled down and

solidified. lava lar-va Molten rock that runs out of volcanoes. magma Molten rock beneath the surface of the Earth. mantle man-tel The part of the Earth below the crust. particles The tiny pieces (atoms or molecules) that everything is made

out of.

8Ha – Explaining the Earth/Sedimentary rocks (continued)

Word Pronunciation Meaning transport The movement of rock grains and fragments by wind, water

or ice. volcano A mountain that shoots out molten rock. weathering When rocks are broken up by physical, chemical or

biological processes.

8Hb – Hot rocks

8Hc – All change!

Word Pronunciation Meaning gneiss nice A metamorphic rock formed when schist is heated and squashed

more. It usually has bands of different coloured minerals.

marble A metamorphic rock formed from limestone. metamorphic rock met-a-mor-fik Rocks that have been formed from igneous or sedimentary rocks

by heat and pressure. mudstone A sedimentary rock made of tiny particles. quartz kwartz The mineral that forms the grains in sandstone. quartzite kwartz-ite A metamorphic rock formed from sandstone. schist shist A metamorphic rock formed when slate is heated and

squashed more. slate A metamorphic rock with tiny crystals that are lined up. It

is formed from mudstone, and can be split into layers.

Page 2 of 3


8H Word Sheets (continued)

Word Pronunciation Meaning constructive plate margin

Where two plates are moving apart and new rock is being formed between them.

continental crust The crust that forms the continents. It is less dense than oceanic crust.

continental drift The theory that pieces of the Earth’s crust moved through the rocks beneath the ocean.

convection current A current created by heat causing changes in density. destructive plate margin

Where two plates meet and one is being pushed down under the other.

oceanic crust The crust that forms the ocean floors. It is mostly basalt, and is denser than continental crust.

plates Pieces of the surface of the Earth, which can move around very slowly.

plate tectonics The modern theory that the Earth’s surface is split into separate plates that are moved around.

8Hd – Theories about the Earth

Word Pronunciation Meaning catastrophism kat-a-strof-sim The theory that all the rocks were formed by sudden events

such as volcanic eruptions. creationism kree-ay-shun-ism The idea that the world was created by a divine being. theory A scientific idea that can be tested. uniformitarianism yoo-nee-form-it-air-

ee-an-ism The idea that rocks were formed over many millions of years by the same processes that we see happening today.

8Hd – Focus on: Plate tectonics

8He – The Rock Cycle/Living in danger

Word Pronunciation Meaning plates Pieces of the surface of the Earth, which are moved around very

slowly. rock cycle All the processes that form sedimentary, igneous and

metamorphic rocks linked together.

Page 3 of 3


8H Word Sheets (continued)

Use the Cut out the labels and stick them in the correct places on the rock cycle diagram.

lava

magma

sea

sedimentary rock

igneous rock

volcano

1) Homework 5 The Rock Cycle

I CAN... • recall the key parts of the rock cycle.


Working towards Level 4

Observe the texture of rocks.

Recall that there have been different theories in the past that have attempted to explain the formation of rocks.

Level 4

Identify some evidence for and against theories that try to explain the formation of rocks.

Recall that people live in areas prone to earthquakes or volcanic eruptions in spite of the dangers.

Make and record observations carefully.

Recognise that geologists can use evidence from rocks to work out how they were formed.

Describe a difference between the textures of sedimentary, metamorphic and igneous rocks.

Describe how igneous rocks are formed. Describe how sedimentary rocks are formed.

Level 5 Explain how and why a scientific theory becomes accepted.

Use the particle model to explain how the speed of cooling affects the crystal sizes in igneous rocks.

Describe the processes that lead to the formation of sediments.

Use models to explain what explain what happens during the formation of metamorphic rock.

Identify similarities and differences between rock textures. Plan a fair investigation without help.

Explain how sedimentary rocks can tell us about past conditions.

Describe how temperature affects the texture of igneous rocks.

Name Class Date

My Target Level is: My final level is:

Tick the boxes that apply. Or use traffic lights to show how confident you are (red = ‘I don’t know this’; orange = ‘I’m not very confident about this’; green = ‘I’m confident I know this’).

Page 1 of 2


8H Level Ladder


Level 6 Plan to collect valid and reliable results.

State some reasons why people live in areas at risk from earthquakes or volcanic eruptions.

Describe how fossils can be used to date rocks. Level 7

Describe how the final texture of a metamorphic rock depends on the pressures and temperatures the rock was subjected to.

Draw conclusions about how sedimentary or igneous rocks were formed based on observations of their texture.

Link the different rock formation process together in the rock cycle.

Link the composition of igneous rocks to some of their properties.

Explain why the theory of plate tectonics is accepted by most scientists.

Link the densities of igneous rocks to the minerals they contain.

Level 8 Describe the idea of metamorphic grade.

Page 2 of 2


8H Level Ladder (continued)

H

Explaining the Earth

Rocks are made from a mixture of minerals. The shape of rocks can be changed by weathering and erosion. Weathering can be chemical, physical or biological.

Sedimentary rocks

Rock fragments, formed as a result of weathering and erosion, are transported by moving water, wind or

ice, and the fragments get worn down. Small rock fragments are called grains. When the water, wind or ice

slows down, some of the grains are deposited at the bottom of rivers, lakes or seas, as sediment.

Layers of sediment collect on the sea bed, and the bottom layers get squashed. The grains of sediment are

forced closer together (compacted) and the water is squeezed out from between

the grains. Minerals from water that flows through the sediment ‘glue’ the grains of rock

together (cementation). Eventually, sedimentary rock is formed. The composition and texture

of sedimentary rocks vary and depend on the way the rocks were formed. For example, the sediments that made a rock with large grains must have been moved by a fast-flowing river.

If any animals or plants get trapped in the sediment, they may form fossils.

Igneous rocks

Molten rock is called magma. If the molten rock flows out of volcanoes it is called lava. Igneous rocks are formed when magma cools down.

Lava cools down quite quickly, and forms igneous rocks with small crystals (like basalt). Magma underground cools down much more slowly and forms rocks with bigger crystals, like granite.

Metamorphic rocks

Sedimentary or igneous rocks can be changed by heat or pressure into new kinds of rock, called metamorphic rocks. Metamorphic rocks have different properties from the sedimentary or igneous rocks they were made from.

Page 1 of 2


Summary Sheets

Type of rock Sedimentary Igneous Metamorphic Examples limestone, sandstone,

mudstone, chalk basalt, granite marble, quartzite, slate,

schist, gneiss Grains or crystals? separate grains crystals that are not lined up crystals – often lined up

or in bands of different colour

Hard or soft? often soft or crumbly hard hard Porous? often not usually not usually

The rock cycle

The Earth is continually changing. Rocks are weathered and eroded and new rocks are being formed. The processes that make rocks, weather them and change them are linked together in the rock cycle. The earth movements that bury rocks

as part of the rock cycle are caused when the plates that form the surface of the Earth push into each other.

Theories about the Earth

There have been many different theories about how the rocks of the Earth were formed. A scientific theory is an idea that can explain many different observations, and it can make predictions that can be tested.

Creationism says that the Earth was formed in a few days by a divine being. Different religions have different creation stories. Most people do not regard this as a scientific theory any more.

Catastrophism says that all rocks were formed by sudden events such as volcanic eruptions. Some rocks are formed this way, but most are not.

Uniformitarianism says that the same processes we see today occurred in the past, and all rocks were formed by very slow processes. According to this theory, the Earth must be very old.

Today scientists think that uniformitarianism is mostly right, but there are some fast processes that also help to shape the Earth, such as volcanic eruptions and earthquakes.

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Summary Sheets (continued)

7H

The local geology society is trying to encourage more people to take an interest in rocks. They want to publish a leaflet called ‘Geology Detectives’. The leaflet will start by explaining how rocks can be useful and how sedimentary rocks form, but it will also give people some ideas about what they can see in rocks that will tell them about what happened to the sediments that formed the

rock. Produce a leaflet, or present a poster or a computer presentation.

7 H

Exploring Science editio © Pearson Education Limit

ed 2008

Assess yourself!

Level I have… Yes Working towards level 4

described at least one use of rocks. linked why a named rock is used for a certain thing to its properties, e.g. it is strong.

Level 4 described how you can tell that a rock is a sedimentary rock by examining its texture.

stated that sedimentary rocks weather more easily than other rocks. given one way of how the ease with which sedimentary rocks are weathered can affect the landscape.

Level 5 described the processes of physical, chemical and biological weathering of rocks.

described how rock fragments are transported and abraded. explained why sediments are deposited. explained how sedimentary rocks are formed. given the presence of plant fossils in coal as evidence that it was formed from plants.

Level 6 described the different conditions in which the different types of weathering are likely to occur.

explained how the speed of water affects the size of grains that can be transported.

compared the sizes of grains that wind, water and ice can carry. explained how knowledge of the size of grains that can be transported can be used to work out what happened to the grains in sedimentary rocks before the rock was formed.

described how erratics show that ice must have covered the area at some point in the past.

described at least three effects on the environment of quarrying. Level 7 described how ripples form in sediments and that these can be

preserved when the sediments form rocks.

explained how cross-bedding patterns can show us the direction of a current or wind, and how the depths of beds can distinguish between water-borne and wind-blown sediments.

explained how evidence other than erratics supports the idea that ice once covered much of Britain.

Documents

Globe Academy Science Department Year 8 Rocks and Rock ... summ… · True False a The movement of pieces of rock is called weathering. ... texture The scientific word used to describe