© Boardworks Ltd 20031 of 25

Geology

© Boardworks Ltd 20032 of 25

Most slides contain notes to accompany the presentation.

This icon indicates that the notes contain particularly

detailed instructions or extension activities.

To access these notes go to ‘Notes Page View’ (PowerPoint 97) or ‘Normal View’ (PowerPoint 2000/2002).

Normal ViewNotes Page View

This icon indicates that a Flash file has been

embedded into the PowerPoint slide. These files are

not editable.

Teacher’s notes and Flash files

© Boardworks Ltd 20033 of 25

There are 3 types of rock:

Sedimentary

Metamorphic

Igneous

Types of rock

© Boardworks Ltd 20034 of 25

Igneous rocks

Some igneous rocks have small crystals. These have cooled quickly close to the surface. These are hard rocks.

An example of this type of igneous rock is basalt.

Some igneous rocks have large crystals. These have cooled slowly deep underground. These are hard rocks.

An example of this type of igneous rock is granite.

In igneous rocks the crystals are in a random order (no pattern).

© Boardworks Ltd 20035 of 25

Granite

Basalt

What differences do you notice between these two igneous rocks?

Granite has visible crystals.

© Boardworks Ltd 20036 of 25

The formation of igneous rocks

magma

Se

dim

en

tar y

rock

s

volcano

Extrusiveigneous rocks arecooled quicklyso small crystals form (e.g. basalt).

Intrusiveigneous rocks are cooled more slowly so large crystals form (e.g. granite).

© Boardworks Ltd 20037 of 25

Igneous rocks

Basalt

© Boardworks Ltd 20038 of 25

Granite

Igneous rocks

© Boardworks Ltd 20039 of 25

Basalt pillars

These pillars were formed when lava cooled on the Earth’s surface.

© Boardworks Ltd 200310 of 25

Sedimentary rocks

These are made from layers of sediment. They are grainy and crumbly and may contain fossils.

Examples of sedimentary rocks are sandstone and limestone.

© Boardworks Ltd 200311 of 25

Sedimentary rock – sedimentation

layers of sedimentsgetting older

© Boardworks Ltd 200312 of 25

The formation of sedimentary rocks

These were formed from layers of sediment which were squeezed together.

newdeposits

layers ofsedimentsgettingolder

sea/lake/river

land

rivers

© Boardworks Ltd 200313 of 25

sandstone

limestone chalk

sandstone

Sedimentary rocks

© Boardworks Ltd 200314 of 25

Metamorphic rocks

Metamorphic rocks show small crystals in layers (bands).

Metamorphic rocks are hard and smooth.

Examples of metamorphic rocks are slate and marble.

© Boardworks Ltd 200315 of 25

Metamorphic rocks are formed by the effect of extreme pressures and temperatures deep within the Earth.

This alters the structure of the existing rock.

Metamorphic rock - formation

© Boardworks Ltd 200316 of 25

The formation of metamorphic rocks

magma

Se

dim

en

tar y

rock

s

sedimentaryrocksare changedhere due toheat and pressure.

volcano

© Boardworks Ltd 200317 of 25

marble

slate

Metamorphic rocks

© Boardworks Ltd 200318 of 25

Continent collision causes metamorphism and huge folds like this one in Scotland.

Metamorphic rocks

© Boardworks Ltd 200319 of 25

Rock formation

sea

volcano

Igneous rocksbasalt

Igneous rocksgranites

rocks riseto surface by

uplift and erosion

rocks are brokenup by the action

of weather

magma

Metamorphic rocks slate and marble

Sedimentary rocksmudstone

slowsolidification

high pressureand temperature

transportationand deposition

rises to surfacewhere it

cools rapidly

melt

© Boardworks Ltd 200320 of 25

Rock cycle

© Boardworks Ltd 200321 of 25

GraniteSlate

Marble

Basalt

Match the rocks with the correct label

B

AChalkC

D

© Boardworks Ltd 200322 of 25

Metamorphic Sedimentary Igneous

Put the following rocks in the correct column

slate

shale

limestone

chalk

basalt

granite

clay

marble

sandstone

© Boardworks Ltd 200323 of 25

pressure and heat

rock is broken down (weathered) and transported into rivers

Make a simplified rock cycle

rock is upliftedrock is broken down (weathered) and transported into rivers

© Boardworks Ltd 200324 of 25

rock is broken down (weathered) and transported into rivers

pressure and heat

Rock cycle

heat

rock is broken down (weathered) and transported into rivers

© Boardworks Ltd 200325 of 25

Identify these rocks

C graniteA slate D chalkB basalt E sandstone