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Flashcards in Volcanoes Deck (13)
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Formation of a supervolcano Step2

The magma chamber grows this then forces the ground upwards into DOME this creates fissures hydrothermal features


Formation of a supervolcano Step3

Gas and ash escape through fissures and into cracks in the surface causing a massive super eruption


Formation of a supervolcano Step4

The land collapses into the now empty magma chamber
This creates a depression called a CALDERA


Where is a Composite volcano found

Destructive plate margins (subduction)


What is a Composite volcano like

Cone shaped
Steep sided, layers of ash and lava
Magma viscous/ cools quickly
Example: Montserrat


Where is a Shield volcano found at

Constructive plate margins


What is a shield volcano like

Dome shape with sloping sides
Gentle explosions (less explosively due to type of magma)
Lava is runny and flows distances
Example: Iceland


What is the difference between a volcano and a super volcano

A super volcano is more powerful as it can affect people on a global scale. (volcanic ash in the atmosphere)


Impacts of a supervolcano

- A pyroclastic flow can kill people (flow of magma from volcano)
- People have to move houses new area (falling ash,lava,explosion)
- Volcanic ash will block solar radiation (famine)
- Ash in the atmosphere can cause a volcanic
winter(economies collapse)


5 warning signs of a volcano (yellow stone)

1. More frequent eruptions
2. Vents spraying out boiling temperatures
3. High levels of hydrogen sulphide and carbon dioxide (gases found in magma)
4. Ground has steadily/ slowly been uplifting
5. Ground temperatures soared to boiling point


Planing for a volcano

1. Concrete shelters are built to protect people from volcanic ash
2.Channels to divert dangerous flows


Predicting/ monitoring a volcano

1. Tilt Meters - detect when volcano swells up as it fills with magma
2. Air crafts - measure amount of gas volcano gives off (predict eruption)
3. Bore holes- measure water temperature ( temperature increases closer magma is)


Formation of a supervolcano Step 1

The magma chamber is fed with magma from the mantle over weak areas in the earths crust