C2c Does The Earth Move?
• The Earth is as a sphere with a thin rocky ___________,
surrounding the _____________ and the ____________.
• This is made up from the inner core and the outer core
• The Earth’s core contains _____________.
• ____________________________ reactions take place in the core which
create a lot of ______________ energy. As a result, the mantle stays molten.
• The mantle is the zone between the crust and the core.
• It is relatively _____________ and ____________ just below the crust but
hot and non-rigid and so able to _______________ at greater depths.
• Liquid rock is called _____________________.
• The lithosphere is made from the _______ and the outer part of the ______
• It is made up from two types of tectonic plates:
1. _______________ plates (under oceans) most dense
2. _______________ plates (land) least dense
• The lithosphere is relatively cold and rigid.
• Tectonic plates are found on _______________ of the mantle because they
are ________________ dense than the mantle.
How do we know that tectonic plates move?
The __________ and _____________ on
the east coast of South America are the
____________ as those on the west coast
of Africa which suggests that they were
How do tectonic plates move?
• Nuclear reactions in the core generate a lot of ______________ energy.
• The rock particles in the magma get hot, vibrate____________ and push
each other apart. This makes the rock __________ dense so it rises.
• As the rock rises towards the crust it ___________ energy, cools down and
particles move _______________ together. This makes the rock
__________ dense so it sinks back towards the core.
• We call these ________________________ currents.
Earthquakes and Volcanoes
The movement of tectonic plates results in __________ activity and ___________
The diagram above shows the boundaries of The diagram above shows all the regions of
the tectonic plates and the directions that volcanic activity and earthquakes – note
they are moving in. that the patterns are almost identical i.e.
most volcanoes and earthquakes happen on
• Some of the rock on the Earth’s surface has been formed
by volcanic activity.
• Molten rock (magma) can find its way to the surface through _____________
in the crust.
• Molten rock under the Earth’s surface is called _______________.
• Molten rock that erupts from a volcano is called _______________.
• When molten rock cools down it forms ________________________.
• Some volcanoes give runny lava and some give thick lava violently and
• Some people choose to live near volcanoes because volcanic soil is very
_________________ (good for growing crops).
Higher Level Theory
• Magma from the mantle must have a lower density than that of the crust in
order to rise through it.
• Collision between oceanic and continental plate leads to _________________
and partial remelting (oceanic goes underneath continental).
• The size of the crystals in igneous rocks depend on how ______________ the
Magma that cools under the surface cools Molten rock that cools ____________
__________ and forms large crystals has very small crystals. e.g. lava, basalt
• Magma has different compositions and depending on what it is made from
depends on what sort of lava and explosion results:
Small (fine) Crystals Large (coarse) Crystals
‘runny’ lava and fairly safe in an
explosive reactions produce
pumice, volcanic ash and “bombs”
• Geologists study volcanoes to be able to predict future eruptions and to reveal
information about the structure of the Earth they are now better at
predicting volcanic eruptions but not with 100% accuracy.
Think about and be prepared to answer questions on:
The problems encountered when studying the structure of the Earth and why
opinions may vary greatly between different geologists.
Igneous Rock (e.g.basalt and granite)
Formed from molten rock cool – see previous notes
Sedimentary Rock (e.g.) limestone
• When rocks weather the small pieces are washed by rivers to the sea.
• Layers of sediment build up and a high ________________ causes the sediment
to cement together.
• We call this sedimentary rock. It is ______________, _____________ and
Metamorphic Rock e.g. marble, slate
• If sedimentary or igneous rock is subjected to high ______________________
(near volcanoes) or high __________________ (near tectonic plate boundaries),
the rock can be __________________/change shape.
• Limestone becomes _____________________ when it is heated
• Mudstone (sedimentary) becomes ______________ (metamorophic) under high