Oral Presentation

1. Volcanoes
By Milena Nuñez Pichel

2. What is it a volcano?
A volcano is like a chimney in the Earth’s
crust
(surface) where magma flows out.
What is it a volcano?
A volcano is like a chimney in the Earth’s
crust (surface) where magma flows out.

3. Eruption
In 1883, in Indonesia, a volcano called
Krakatoa erupted at first.
Krakatoa
Eruption
In 1883, in Indonesia, a volcano called
Krakatoa erupted at first.
Krakatoa

4. The inside of the Earth is very hot, and
some of the solid rock melts to form hot,
liquid rock called magma.
The hole of the volcano is called vent.
When magma leaves the vent it becomes
lava.
The life of a volcano

5. A volcanic eruption
Contents: gas, dust, water vapour, lava and ash
Gas, dust and water
vapour
Vent
Lava
Magma
Magma chamber
Layers of lava and ash

6. Types of volcano
Scientists put volcanoes into three groups:
1. An Active volcano is one that is erupting
or will soon erupt.
2. A Dormant volcano is one that has not
erupted for a long time.
3. An Extinct volcano is one that has not
erupted for more than 10.000 years.

7. Rocks and lava
Volcanoes produce lava and rocks we find
on the Earth’s Surface. Magma forms igneous
rocks. These fragments are called tephra.

8. Bomb Lapilli
Types of tephra
Ash Dust

9. Underwater volcanoes
- The floor of the ocean is similar to dry land.
- There are flat plains, mountain ridges,
canyons and trenches in the ocean floor.
- There are more volcanoes
under the ocean
than on the land.

10. Living with volcanoes
The minerals and chemicals in the lava and ash make
soil fertile so it’s good for farming.
Volcanoes also produce electricity.
This electricity is called geothermal energy
and the people use it.

11. Some famous volcanoes
Fuji,
dormant
Krakatoa,
active
Vesuvius,
active
Kilamanjaro,
dormant

12. Volcanic hazards
• Most hazards during
eruptions are caused by
what comes out of a
volcano

13. Volcanic hazards – lava flows
• Slow moving
• Low risk to human life
• Cover large areas and
is very destructive

14. Hazards – ash clouds
• Slow moving
• Weight of ash can collapse
buildings
• Destroys crops, pollutes
water
• Affects air traffic

15. Hazards – lava bombs
• Molten rocks thrown out of volcano
• Travel short distances
• Can start fires

16. Pompeii’s simulation