What is a volcano?
A volcano can be defined as an opening in the Earth's crust where through which molten lava, ash, and gases are ejected.
How are volcanoes formed?
Volcanoes are formed when hot material leaks up to the Earth's crust. The material is called magma when it's under the ground. When it reaches the surface it is called lava.
What are the main parts of a volcano?
A volcano has 4 main parts.
A main vent: the main vertical channel in which the magma rises to the surface.
A crater: the hole that the lava comes out of at the top of the volcano
A volcanic cone: the mountains that are created by the rocks and hard lava that accumulates near the crater when the magma escapes the mani vent
A magma chamber: the large underground pool of molten rock found beneath the surface of earth
A main vent: the main vertical channel in which the magma rises to the surface.
A crater: the hole that the lava comes out of at the top of the volcano
A volcanic cone: the mountains that are created by the rocks and hard lava that accumulates near the crater when the magma escapes the mani vent
A magma chamber: the large underground pool of molten rock found beneath the surface of earth
What causes a volcano to erupt?
The Earth's crust is made up of huge slabs called plates, which fit together like a jigsaw puzzle. These plates sometimes move. Between the Earth's crust and the mantle is a substance called magma which is made of rock and gases. When two plates collide, one section slides on top of the other, the one beneath is pushed down. Magma is squeezed up between two plates.
How does a volcano erupt?
Magma is constantly trying to push itself toward the surface because it is less dense than the rock above it. The magma seeps through Earth's crust and makes its way above the rock formations and eventually into rivers of magma that form underneath a volcano's surface. The rivers are known as magma chambers. The magma chambers are under a lot of pressure because of the buildup of molten rock and gases. How explosive the eruption is depends on how fast or slow the gases escapes from the magma chamber up the main vent.