The location of volcanoes

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The location of tectonic
activity
•
•Identify, describe and explain the patterns of
Earthquakes and Volcanoes
Can you name the
places where
volcanoes and
earthquakes
occur?
True or false?
• Volcanoes and earthquakes happen all
over the world.
• Volcanoes are found in narrow belts.
• Volcanoes are found along the East Coast
of North and South America.
• Volcanoes are found along the West
Coast of North and South America.
Where do earthquakes and
volcanoes occur?
Skills Builder 1
(a) Earthquakes occur in broad belts. Tend to be found in the middle of
oceans e.g. Atlantic or along the edges of continents e.g. West
coast of North America. Can also occur just off-shore of continental
landmasses, e.g. western Pacific Ocean. There are some
exceptions; there are earthquakes inland such as in eastern Africa.
(b) Volcanoes also occur in broad belts. Found along the edges of
continents e.g. West coast of South America. Can be found just offshore of continental landmasses, e.g. western Pacific Ocean.
Anomalies include cluster of volcanoes in the mid-Pacific around
Hawaii and band of volcanoes inland in eastern Africa.
N.B. Able students might note that earthquakes and volcanoes often
occur in the same locations.
• On the diagram, mark
and name: the North
American Plate, the
Caribbean Plate, the
Pacific Plate, the
African Plate, the
Eurasian Plate, the
Arabian Plate, the
Indo-Australian Plate.
Check your answers
using Figure 4
(student book p.101)
The structure of the Earth
TASK 1
• Annotate (label) this
diagram using the
following words:
Inner core
Outer core
Mantle
Crust
Plates
Plate boundary
The Structure of the Earth
FACTS
• The inner core is the centre of the earth, made of
solid iron and nickel, it is the hottest part with a
temp. of 5500oC
• The outer core is made up of liquid iron and nickel
• The mantle is made up of semi-molten rock,
partially melted rocks are called magma,
temperatures reach 5000oC here.
• The crust is the thinnest layer, and is made up of
solid rock, it is the outer layer, like skin of an apple
Tectonic Plates
• The Earth’s crust is divided up into
plates
• These plates ‘float’ or move very slowly
(a few mm per year) on the molten
material of the mantle. This movement
is caused by convection currents in the
mantle.
Explain the difference
between continental crust
and oceanic crust
• On the diagram
below, mark and
name: Inner core,
Outer core, Mantle,
Trench, Ridge. Check
your answers using
student book pp.101–
102.
Plate tectonics
• The place where two plates meet is called
a plate boundary, most earthquakes and
volcanoes happen here in a narrow belt
called ‘zones of activity’
Image of the world 160 million
years ago
Image of the world 80 million
years ago
Image of the world today
Evidence
Evidence
Add to you description
b. Why do volcanoes and earthquakes
happen in these locations
Neatly add these correct labels:
Generally explosive volcanic eruptions.
Magma rising to form volcanoes.
Plate being forced into the mantle
Deep, violent Earthquakes
One plate is denser than the other so sinks. Plate melting.
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