Volcanoes Flashcards
What is the first step to a volcano being formed?
A volcanic mountain forms when magma moved up to the surface through a vent
What is the second step to a volcano being formed?
The magma is stored underground in a large chamber called a magma chamber
What is the third step to a volcano being formed?
The gas builds up in magma chamber. The pressure from the gases causes the magma to erupt out of the vent through the crater
What is the fourth step to a volcano being formed?
When magma reaches surface it is known as lava. The lava cools down and hardens around the vent
What is stage 5 in a volcano being formed?
Other materials such as ash are also ejected from a volcano when it erupts
What is stage 6 in a volcano being formed?
After repeated eruptions layers of ash and lava build up around the vent to form a Cone shaped mountain
What is the life cycle of a volcano?
Active
Dormant
Extinct
What is an active volcano?
Erupts regularly
Ex. Mount etna
What is a dormant volcano?
Has not erupted for some time
Ex. Mount St. Helens
What is an extinct volcano?
Has not erupted in historic times
Slemish co. Antrim
How is a volcano formed at a destructive plate boundary?
The heavier crustal plate sinks below lighter crustal plate. As it melts a blob of magma bread ooff and moves up to crust. Over time this magma can erupt and form a volcano
Ex.mount St. Helens
How are volcanoes formed at constructive plate boundaries?
As plates separate magma rises up through crust. Lava pours gently onto surface through a fissure. Magma cools v quickly and builds up over time
