Transcript Lesson 2 - Humanities.Com

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To recap plate boundaries and the
location of tectonic activity
To distinguish between composite and
shield volcanoes
To understand the effects of an
eruption
Do all volcanoes kill?
Key terms: composite volcano, shield volcano,
basalt, andesite
Plate Boundaries Recap
1.
2.
Can you name both these plate boundaries
and explain what happens at each.
Look back over your notes to help.
Describing tectonic activity
Describe the location of earthquakes and volcanoes
on the map below. 3 marks (so make 3 points).
Describe means to
say what something
is like. You could
have said:
Earthquakes and
volcanoes occur on
plate boundaries
They occur around
the Pacific Ocean
– this is known as
the Ring of Fire
They don’t tend to
occur away from
boundaries.
Volcanoes Recap
*Watch the clip.
Try to write down
a definition for
volcanoes
Try to note down a
famous volcano.
Try to note down
what is erupted
from a volcano
(there’s more than
one thing!)
Features of a volcano
1.
2.
3.
4.
5.
Dust
Ash
Crater/lava
Volcanic bomb
Pyroclastic
flow
6. Layers of lava
and ash
7. Crust
8. Main vent
9. Magma chamber
10. Secondary vent
Two very different volcanoes
This is Mauno Loa on
Hawaii. It is a shield
volcano. It is gently
sloping, and does not
produce violent eruptions.
It has actually created
the island of Hawaii!
This is Mount Merapi in
Indonesia. It is a
composite volcano. It is
steep sided volcano, and
has violent eruptions. It
is the world’s most active
volcano!
Two very different volcanoes
This is a cross section
of Mauno Loa on Hawaii.
Copy the diagram. Make
sure it has a title and
labels.
This is a cross section
of Mt Merapi in
Indonesia. Copy the
diagram. Make sure it has
a title and labels.
Killer Volcanoes?
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•
•
•
Not all volcanoes kill. Some like Mount Merapi in
Indonesia do. But some like Mauna Loa in Hawaii don’t.
Why?
Well it’s all down to the lava that makes the volcano.
Shield volcanoes are made from a thin runny lava (called
basalt). This lava will not get stuck in the volcano
vent. The eruption will be freely flowing and gentle
(like pouring water from a jug). They are found on
constructive boundaries.
Composite volcanoes are made
from a thick sticky lava
(called andesite). This lava
will get stuck in the main
vent and cause pressure to
build up. The eruption will
be violent and will be a
pyroclastic flow (a bit like
when you shake up a bottle
of coke and open it quickly).
They are found on destructive
boundaries.
Answer the questions on The 2 Types of Volcano sheet
The Eruption
How many effects can you spot? How do people
respond to the threat in this clip?
The Eruption
Make a concept map or list of all the effects of
an eruption. How many can you get?
Pyroclastic
flow
Incinerates
blast zone
Towns
destroyed
Industries
bankrupt
Lava
erupted
People
evacuate
Ash fall
Kills plants
and animals
Dust
People
suffocated
Roads cut off
Less food
Huge financial
cost
Tourism destroyed
Death
Farmland
ruined
Trauma
Roofs collapse