Geology introduction to earth science

Geology

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Learning objectives

What are the different types of rock?
How are igneous rocks formed?
How are sedimentary rocks formed?
How are metamorphic rocks formed?
What is the rock cycle?

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Types of rock
There are 3 types of rock:
Sedimentary
Metamorphic
Igneous

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Learning objectives

What are the different types of rock?
How are igneous rocks formed?
How are sedimentary rocks formed?
How are metamorphic rocks formed?
What is the rock cycle?

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Igneous rocks
Igneous rocks are formed by the solidification of
molten material from below the earth's surface.
Extrusive igneous rocks are cooled quickly so small
crystals form (e.g. basalt).
Intrusive igneous rocks are cooled more slowly so
large crystals form (e.g. granite).

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Igneous rocks – crystal size

Granite

What differences do you
notice between these two
igneous rocks?

Granite has visible crystals.

Basalt

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Igneous rocks

Basalt

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Igneous rocks

Granite

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Basalt pillars

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

What are the different types of rock?
How are igneous rocks formed?
How are sedimentary rocks formed?
How are metamorphic rocks formed?
What is the rock cycle?

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

Examples of sedimentary rocks are sandstone and

limestone.
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Sedimentary rock – sedimentation

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Sedimentary rocks
sandstone

sandstone

limestone

chalk

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Sedimentary rocks

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Learning objectives

What are the different types of rock?
How are igneous rocks formed?
How are sedimentary rocks formed?
How are metamorphic rocks formed?
What is the rock cycle?

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Metamorphic rock - formation
Metamorphic rocks are formed by the effect of
extreme pressures and temperatures deep within the
Earth.
This alters the structure of the existing rock.

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Metamorphic rocks
Metamorphic rocks show small crystals in layers (bands).

Metamorphic rocks are hard and smooth.
Examples of metamorphic rocks are slate and marble.

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Metamorphic rocks
marble

slate

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Metamorphic rocks

Continent collision causes metamorphism and
huge folds like this one in Scotland.
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Match the rocks with the correct label

B

D

C

A

1 slate

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2 basalt

3 granite

4 chalk

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Which type of rock am I?

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Learning objectives

What are the different types of rock?
How are igneous rocks formed?

How are sedimentary rocks formed?
How are metamorphic rocks formed?
What is the rock cycle?

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From weathering to sedimentation

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Rock formation
rocks are broken up by the
action of weather
volcano
Igneous rocks
basalt
rises to
surface
where it
cools
rapidly

rocks rise
to surface by

uplift and erosion

sea
Sedimentary rocks
mudstone

Igneous rocks
granites
slow
solidification

magma

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transportation
and deposition

high pressure
and temperature
Metamorphic rocks
slate and marble

melt

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Rock cycle

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