Composite Volcano

1
Composite Volcano

• This type has alternate layers of ash and lava.
• Sometimes there can be different layers of lava
  on top of each other, but with years in between
  eruptions.

USGS
2
Hazards
Image from the USGS website (modified)
Prevailing Wind
Eruption Cloud
Eruption Column
Ash
Volcanic Bombs
Pyroclastic Flow
Acid Rain
Many volcanoes are so high they are covered in
snow and new volcanic activity melts the snow
causing mud flows and landslides.
Sometimes the lava builds up to form a lava dome
which can explode with dramatic effect, such as
at Mount Pelee and other volcanoes mentioned in
this study.
Lava Dome

• Water and sulpher gas mix to create fumaroles.

If there is a lot of gas present the lava
explodes out of the vent to cause ash clouds and
other features.
Landslide
Larger pieces of lava are known as volcanic bombs.
Lava can flow over many kilometres and the
eruption cloud can extend around the world.
Molten rock reaches the surface to form
destructive lava flows.
Fumaroles
Ground Water
Lava Flows
Mud Flow
Magma
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Volcanoes Exercise
Image from the USGS website (modified)

• Use the list below to label the diagram.
• Lava Eruption Cloud
• Acid Rain Magma
• Bombs Mud flow
• Lava Dome Landslide
• Fumaroles Ground Water
• Pyroclastic Flow