All through term one my class have been doing geology! We had to make a poster for natural disasters and I chose to do volcanoes. On the poster we had to put ten facts, a picture of the thing we had chosen to do and of course a title. Here is the poster:
This is the facts;
Inside the earth it is really hot so some rocks melt and turn into magma since magma is lighter than rock it rises and goes inside magma chambers. Eventually some of the magma pushes through vents to the earth surface which causes volcanoes to erupt.
The danger area around the volcano has a 20 mile radiusMore than 80% of the ground is volcanic in origin
There are three major kinds of volcanoes; cinder cones, composite volcanoes and shield volcanoes.
Cinder cones are formed by blobs of congealed lava coming out of a vent, as the gassy lava is blown roughly into the air it breaks into small pieces that turn into cinders and fall down around the vent to create a circular or oval cone.
Composite volcanoes (also called stratovolcanoes)are named for their composition. These volcanoes are created from layers of pyroclastic material, including lava, pumice, volcanic ash, and tephra. The layers stack on each other with each eruption.
When volcanoes erupt they can trigger tsunamis and earthquakes.
A shield volcano is a type of volcano named for resembling a warrior's shield lying on the ground.
The sound of an eruption volcano can be quiet and hissing or explosive and booming.
There are 1,500 active volcanoes in the world.